Salt dissolves in water to form saltwater. Is this considered a chemical change or a physical change

Answers

Answer 1

Salt dissolves in water to form saltwater. This kind of change is regarded as a chemical change.

A physical change is a kind of change in which only the physical properties of matter change. In a physical change, neither the composition nor the chemical nature of matter is changed.

A chemical change involves a chemical process that results in the production of new substances. When you dissolve salt in water the sodium chloride dissociates in Na+ and Cl- ions which can be written in the form of a chemical reaction as,

NaCl →  Na+(aq) + Cl-(aq)

Thus, dissolving salt in water is an example of a chemical change.

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Related Questions

To find the acceleration of a glider moving down a sloping air track, you measure its velocities (V1 and V2) at two points and the time t it takes between them, as follows:V1=0. 21+/- 0. 05m/s, V2=0. 85 +/- 0. 05m/s, t=8. 0 +/- 0. 1sa) Assuming all uncertainties are independent and random, find the average acceleration, a=(v2-v1)/t , and its uncertainty. B) How well does your result in part (a) agree with your friends theoretical prediction that a=0. 13 +/- 0. 01m/s^2

Answers

0.08 m/s2 is the average acceleration. The acceleration's degree of uncertainty is 0.0135 m/s2.

Describe acceleration.

Accelerations are included in vector quantities. An object's acceleration in relation to a net force is determined by the direction of that force. Force imbalances lead to acceleration in a body.

Uniform, non-uniform, and average acceleration are the three primary types of accelerated motions. It is said to have uniform acceleration when an object moves in a straight line with an increase in speed that happens at regular intervals of time.

Acceleration is the term used to describe any change in the speed or direction of a motion. Anything that is accelerating is moving faster, slower, or in a direction other than straight forward.

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Throw a paper ball towards a hard wall. a) Did the wall apply force on the ball? If yes, then what is the name of the force? b) What are the effects of the force applied by the wal

Answers

Answer:

Reaction force

Explanation:

A ball is thrown against a wall: The ball puts a force on the wall (action force), and the wall puts a force on the ball (reaction force) so the ball bounces off

Does thermal energy increase or decrease during melting?

Answers

Thermal energy increases during melting.

When ice melts during melting, its temperature remains constant until all the ice turns into water. Then, heating of liquid water causes the molecules to vibrate faster and steadily increasing the temperature.

What is thermal energy?

Thermal energy refers to the energy contained within a system that is responsible for its temperature. Heat is the flow of thermal energy. A branch of physics, thermodynamics, concerns with how heat is transferred among different systems.

An example of thermal energy is boiling water on a stove. When boiling water, thermal energy is produced when the atoms and molecules in a substance vibrate faster because of raising in temperature.

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hello please help i’ll give brainliest

Answers

Answer:mountains

Explanation:

1
Glucose provides energy for cells. Different cells have different mechanisms for glucose intake. Intestinal cells contain proteins that transport glucose against its concentration gradient. These proteins couple the movement of glucose to the movement of sodium down its concentration gradient. Red blood cells have transporter proteins embedded in their membranes. When bound by a glucose molecule, these proteins change shape and allow glucose to move down its concentration gradient into the cell.

Based on this information, what type of transport is used for glucose in blood and intestinal cells?

A.
Both blood and intestinal cells take in glucose by passive transport.
B.
Blood cells take in glucose by passive transport and intestinal cells take in glucose by active transport.
C.
Both blood and intestinal cells take in glucose by active transport.
D.
Blood cells take in glucose by active transport and intestinal cells take in glucose by passive transport.

Answers

Answer:

C. In the passage, it seems that both of the cells have the same job, so I would go with C.

A baseball has a momentum of 6.0kg*(m)/(s) south and a mass of 0.15kg. What is the baseball's velocity?

Answers

A baseball weighs 0.15kg and has a south momentum of 6.0kg m/s. The speed of the baseball was (v) = 40 m/s south.

It's a physical magnitude that measures the product of the mass by the velocity of a particle. Its units in the International System is kg. m/s and the formula is

p = mv

where

m is the mass of the object

v is its velocity

In this problem, we know:

p = 6.0 kg m/s is the momentum of the baseball

m = 0.15 kg is its mass

Therefore, we can re-arrange the equation to find the baseball's velocity:

v = p/m

v = 6.0/0.15

v = 40  m/s south

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40 points!

What is the expected life span of a star with a low stellar mass, a relatively cool temperature, and dim relative brightness?

1 to 10 million years

10 to 100 million years

1,000 to 10,000 million years

10,000 to 200,000 million years

Answers

The expected life span of a star with a low stellar mass, a relatively cool temperature, and dim relative brightness is 10,000 to 200,000 million years and is therefore denoted as option D.

What is a Star?

This is referred to as an astronomical object comprising a luminous spheroid of plasma held together by its gravity an d they are usually visible at night.

We should also note that stars with a high stellar mass burn burn their fuel at a much faster rate and can shine for just millions of years while on the other hand stars with a low stellar mass burn burn their fuel at a much slower rate and can shine for just billions of years.

This therefore means that the expected life span of a star with a low stellar mass and dim relative brightness will most likely be between 10,000 to 200,000 million years hence why option D was chosen.

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What is the acceleration at t 2?

Answers

The formula x(t) = 4t3 + 6sin(t) provides the location of an item. Discover the object's acceleration at time t=2. The variation in velocity called the acceleration.

If x(t) = 4t3 + 6sin(t), then its derivative, v(t) = 12t2 + 6cos(t), provides the velocity (t). Then, the derivative of velocity, a(t) = 24t 6sin, gives the acceleration (t) Therefore, a(2) = 24 2 6sin(2) = 42 6sin(2) gives the acceleration at time t = 2. The overall change in velocity during the specified interval divided by the total amount of time required for the change is the definition of average acceleration over a particular period of time. It is represented as for a specific amount of time. Where is the average acceleration and v2 and v1 are the instantaneous velocities at time t2 and t1, respectively.

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A 5mL tank of Carbon dioxide i tored at a preure of 30mmHg. It i moved to an altitude with a preure of 28mmHg. What will the new volume of Carbon dioxide be?

Answers

The new volume of Carbon dioxide be 5.36 mL.

What happened to the amount of gas in the syringe as you raised the plunger?

Boyle's Law can also be used to explain how a syringe operates. A syringe's plunger being drawn out causes the volume inside the barrel to expand, which lowers the pressure inside the barrel.

Describe Boyle's Law.

According to Boyle's Law, P1V1=P2V2 while the temperature is constant. In accordance with Boyle's Law, pressure and volume are inversely linked. In other words, volume decreases as pressure rises (and vice versa).

Given:

Volume (V1) =5ml

Pressure (P1) = 30 mmHg

Pressure (P2) =28 mmHg

Volume (V2) = ?

From Boyle's Law,

[tex]P_1V_1=P_2V_2[/tex]

[tex]30*5=28*V_2[/tex]

[tex]V_2=\frac{30*5}{28}[/tex]

[tex]V_2= 5.36 ml[/tex]

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HELPP WITH THESE QUESTIONS PLEASEEE!!

Answers

Pe=1/2Kx^2
Half times spring constant times distance squared over time

What is momentum moment Mcq?

Answers

Moment of momentum, which describes the rotating inertia of a system moving about an axis, gauges an object's propensity to keep spinning.

How do you gain traction?

List the object's mass and speed in step one. Convert any values into SI units in step two (kg, m, s). Step 3: To calculate an object's momentum, multiply the object's mass and velocity.

Can there be negative momentum?

Momentum can go wrong. As a vector quantity with both magnitude and direction, momentum has both. The sign, positive or negative, in physics serves as a cue as to the direction. Positive amounts normally signify a forward or upward motion, whereas negative quantities typically indicate a backward or downward motion.

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What is moment momentum?

please help and thanks

Answers

Answer:

the first on the left goes with the 3rd on the right

second left last right

3rd goes with 1st

4th goes with 5th

5th goes with 4th

and last but not least 6th goes with the second

Explanation:

if im correct mark brainliest if im wrong leave a comment.

Which of the following graphs best illustrates how the intensity of sound varies as a detector is moved further and further from a stationary source projecting sound in all directions

Answers

The graph that best illustrates how the intensity of sound varies as a detector is moved further and further from a stationary source projecting sound in all directions would be an inverse square law graph. This graph would show that the intensity of sound decreases as the distance from the source increases. The intensity of sound is inversely proportional to the square of the distance from the source.

This means that if the distance from the source is doubled, the intensity of sound is decreased by a factor of four. This relationship is commonly observed in physics and engineering and is known as the inverse square law of sound propagation. This law states that the intensity of sound decreases as the distance from the source increases in a manner that is inversely proportional to the square of the distance.

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Suppose you have a light spring stretched out and one end is attached to a wall. With this setup, you can move the free end in any of three directions (x,y, z). The spring lies along the z axis.
Which type of wave do you create when you move the free end along the z axis?
Which type of wave do you create when you move the free end along the x axis?
Which type of wave do you create when you move the free end along the y axis?
CHoose one for each.
transverse
longitudinal

Answers

When you move a stretched out light spring one end attached to a wall lying in z-axis along z-axis, you get a longitudinal wave and when along x-axis or y-axis, you get a transverse wave.

When you move the free end of the spring along the z axis (the axis along which the spring is stretched), you create a longitudinal wave. This is because the displacement of the spring particles is in the same direction as the direction of wave propagation.

When you move the free end of the spring along the x axis, you create a transverse wave. This is because the displacement of the spring particles is perpendicular to the direction of wave propagation.

When you move the free end of the spring along the y axis, you create a transverse wave. Similarly to x axis, the displacement of the spring particles is perpendicular to the direction of wave propagation.

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PLEASE HELP ILL MARK BRAINLIEST!!! A ball is initially thrown downwards with an initial speed of 20 m/s from the top of a 300 m tall building. The ball has a constant downward acceleration of 10 m/s ^ 2 a). What is the velocity of the ball immediately before it hits the ground at the base of the building?

Answers

Using the 3rd equation of motion:

= v² - u² = 2gs ------ [g = Acceleration due to gravity]

= v² - 20² = 2 × 10 × 300

= v² - 400 = 6000

= v² = 6000 - 400

= v = √5600

= v = 74.83 m/s

And yeah it's done :)

The pitchers mound in baseball is 85 meters from home plate . If it takes 4.1 seconds for a pitch to reach the plate , how fast is the pitch is m/s.

Answers

Answer: 20.73m/s

Explanation:

The question simply wants us to calculate the speed of the pitch. The speed will be calculated as:

= Distance/Time

where,

Distance = 85 meters

Time = 4.1 seconds

Speed = Distance/Time

Speed = 85/4.1

Speed = 20.73m/s

Therefore, the speed of the pitch is 20.73m/s.

2.71 m and 4.4 m long and have masses of 69.5 kg and 100 kg, respectively. Calculate the total rotational kinetic energy of the two hands about the axis of rotation. Model the hands as lon

Answers

Answer:

1.04 x 10-3 J.

Explanation:

The total rotational kinetic energy of the two hands about the axis of rotation is calculated using the formula:

Kinetic Energy = 1/2 I ω2,

where I is the moment of inertia and ω is the angular velocity.

For this scenario, the moment of inertia is calculated by

I = 1/3 ML2,

where M is the total mass and L is the length of the arm.

Since the total mass of the two hands is 169.5 kg, and the length of the arms is 2.71 m and 4.4 m, the moment of inertia is calculated to be I = 5.35 x 10-5 kg m2. Substituting this value of I into the equation, the total rotational kinetic energy of the two hands about the axis of rotation is calculated to be 1.04 x 10-3 J.

the number of turns in primary coil and secondary coil of transformer never made equal, why??

plz give yr own answer..​

Answers

Answer:

the number of turns in primary coil and secondary coil of transformer never made equal because if we do so there would not be any use of using transformers. same current will be gain.

Actually transformers are use to increase or decrease voltage.

Explanation:

The number of turns in primary coil and secondary coil of transformer never made equal because if we made equal there will run equal voltage of current and there will not be the any use of secondary coil of transformer in the comparison to primary coil .As different transformers are used to increase or decrease the voltage of current.

hope it is helpful to you

3. A student tosses a 0. 500 kilogram rock into

a pond at a rate of 1. 00 meter per second. If

the student's mass is 45. 0 kilograms, what

is the momentum of the rock by the

student?

Answers

The momentum of the rock by the student is 0.500kgm/s.

Momentum -

momentum is the result of a particle's mass and velocity. Being a vector quantity, momentum possesses both magnitude and direction. According to Isaac Newton's second equation of motion, the force applied on a particle is equal to the time rate of change of momentum. Check out Newton's laws of motion.

Momentum can be viewed as a body's "power" while it is moving, or the amount of force it can exert on another body. For instance, a baseball (small mass) thrown quickly can have the same momentum as a bowling ball (big mass) going extremely slowly (low velocity) (high velocity).

Momentum = Mass × Velocity

Momentum of rock = 0.500 × 1

= 0.500kgm/s

Momentum of Boy = 45 × 0 [As boy is at rest so, he has 0 momentum]

Momentum of boy = 0

Total Momentum = Momentum of rock + Momentum of boy

= 0.500 + 0

= 0.500 kgm/s

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Developing a Strategy

Now that you have an obstacle in mind, take another few minutes and think about which success strategy might best help you overcome this obstacle. Write this strategy in the box below:

Answers

Explanation:

Look at your resources around you, find ways to cope with the situation.

Look at your environment or what is there around you that can help you.

Is there anyone that can help you.

Think more.

Try thinking outside of the box

Don't be logical

I wasn't sure if you meant this mentally or physically.

Impulse is ________. View Available Hint(s)for Part A the time interval that a force lasts. the area under the force curve in a force-versus-time graph. a force that is applied very suddenly. a force that is applied at a random time.

Answers

The area below the force curve on a force versus time graph is known as the impulse.

The concept of "impulse" refers to how much of an impact a force has over time. The cricket batsman striking the ball is one of the most well-known and frequently used illustrations. The bat significantly changes the ball's trajectory despite making contact with it for a relatively brief period and launching a bicycle. Everyone occasionally makes rash decisions, particularly when we're young. In general, as we get older, we learn to control our urges. It might or might not be a sign of a problem. A mental health concern may be indicated by persistently impulsive behavior.

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As the number of resistors in a parallel circuit is increased, what happens to the
equivalent resistance of the circuit and total current in the circuit?

Answers

Answer:

resistance- decreases current-increases

If a girl running along a straight road with a uniform velocity 1.5m/s,find her acceleration

Answers

Her acceleration is zero, because her velocity is not changing.

at the top of a pole vault, an athelete actually can do work pushing on the pole before releasing it. suppose the pushing force that the pole ecerts back on the athelete is given by F(x)=(1.5*10^2N/m)x-(1.9*10^2N/m^2)x2 acting over a distance of 0.20m. how much work is done on the athelete?

Answers

2.49 Joules have been performed on the athlete, in accordance with the provided statement.

What in science is a force?

In science, the word "force" has a concrete meaning. At this point, referring to a force as a push or simply a yank is perfectly appropriate. An constituent does not "have in it" or "contain" a factor. A force is felt by one entity coming from another. The idea of a force encompasses both living and non-living entities.

You must incorporate the work expression because it is a vital part of Fdx.

Gained is

  W  =  integral of  (  150x  -  190 x 2 ) dx  

         =    75 x2   -  63.333 x3  

So now...

   work done  =   75 *0.202  -  63.333 *0.203   = 2.49Joules

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a skier of mass m starts from rest at the top of a solid sphere of radius r and slides down its frictionless surface. (a) aat what angle will the skier leave the sphere? (b) if friction were present, would the skier fl off at a freater or lesser angle?

Answers

A skier of mass m starts from rest at the top of a solid sphere of radius r and slides down its frictionless surface.

The net force on the skier in the radial direction must be equal to the centripetal force in order to sustain circular motion.

[tex]$F_{\mathrm{radial}}=\frac{m v^2}{r}$[/tex]

where [tex]v[/tex] denotes the skier's tangential instantaneous speed. Gravity and the normal force are the two forces at work on the skier. While the gravitational force is constantly radially outward, the normal force is always dependent on the angle [tex]\theta[/tex]. Therefore, the net force in the radial direction is, if the skier is at an angle of [tex]\theta[/tex] down the sphere.

[tex]$F_{\text {radial }}=m g \cos \theta-N$[/tex]

where N is the normal force's magnitude. When these two equations are combined, we get,

[tex]$\frac{m v^2}{r}=m g \cos \theta-N$[/tex]

Using the principle of energy conservation, we now substitute v with values we already know. The loss of potential energy equals the increase in kinetic energy, which on a sphere is written as,

[tex]$\frac{1}{2} m v^2=m g r(1-\cos \theta)$[/tex]

As the skier begins at rest, there is no kinetic energy at the top of the sphere. After removing [tex]v^2[/tex], we are left with the equation,

[tex]$2 m g(1-\cos \theta)=m g \cos \theta-N$[/tex]

Quantifying the situation when the skier exits the sphere is the last aspect of the issue. We can see that when theta equals 0, we get N = mg, which means that the normal force acting on the skier precisely balances the force of gravity. N decreases as the skier descends the sphere's surface, balancing the equation until it equals zero at a certain angle. This occurs precisely when,

[tex]$2 m g(1-\cos \theta)=m g \cos \theta$[/tex]

The skier is no longer in contact with the sphere when the normal force acting on the skier is zero, as the sphere no longer exerts any force on the skier. This is assumed to be the prerequisite for the skier to leave the ground.

After calculating [tex]\theta[/tex], we have,

[tex]$2 m g=3 m g \cos \theta$[/tex]

[tex]$\Longrightarrow \theta=\cos ^{-1}(2 / 3) \approx 48.19^{\circ}$[/tex]

First, we can note that this response is unaffected by the physical parameters m, r, and g. No matter how heavy he is, how huge the sphere is, or how powerful gravity is, the skier will exit the sphere at the same angle.

However, we will discover from dimensional analysis that this independence is actually not all that remarkable. Consider the units of the variables we've provided,

[tex]$[m]=$ kilograms,$\quad[r]=$ meters,$\quad[g]=$ meters $\cdot$ seconds $^{-2}$[/tex]

Any algebraic statement containing m, r, and g cannot be transformed into a dimensionless quantity. As a result, we draw the conclusion that the solution to our problem cannot depend on these values as an angle is a dimensionless quantity.

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why are ventilations for a room put near the roof and not near the floor​

Answers

Answer:

Ventilators are provided near ceilings in the rooms of our houses because the hot air is lighter and rises out of the room through the ventilators. Cool fresh air rushes into the room through the doors and windows to occupy its place.

A car slows down at -5.00m/s^2 until it comes to a stop after traveling 15.0m. What was the initial speed of the car?

Answers

The steady deceleration of a car traveling at 15 m/s starts. After ten seconds, it abruptly ends. starting speed of the vehicle

What is the physics of speed?

When subtracting the distance even by travel time, speed is calculated. The distance and time information must be understood in order to calculate the pace units. The measurements in the this case will be performed in meters per second (m/s), as the length was measured in meters and the time is stated in minutes (s).

What connection exists between speed and velocity?

Velocity is the rate and direction of an object's motion, whereas speed is the rate at which an object moves along a path over time. In other words, whereas speed is in fact a scalar value, velocity is a vector.

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Which would be eaier to carry --- a chool bag with a broad trap for a chool bag with a very thin trap?
Jutify your anwer

Answers

A school bag with a broad strap would be easier to carry when compared with a school bag with thin strap.

Bags are used to carry loads. There are bags with two straps and bags with  one strap. Bags with one strap spread lesser area for carrying whereas bags with two straps spread more area.

The school bags with broad straps are easier to handle. This is due to the reason that the load of the bag is distributed over larger area, thereby decreasing the pressure on the shoulders. The pressure provided by smaller straps is higher ans causes irritation.

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Which statement about a turtle's energy source is true?
Responses

A. A turtle performs photosynthesis to gain its energy.

B. Nutrients in the water are the ultimate source of energy for a turtle

C. A turtle relies indirectly on the sun as an energy source.

Answers

Answer:

C. A turtle relies indirectly on the Sun as an energy source.

Explanation:

Turtles are animals, meaning they are unable to perform photosynthesis, thus option A is inapplicable. Turtles consume food such as algae and seagrass. These aquatic plants gain their energy directly from the Sun through photosynthesis, and as a result when the turtle consumes these plants, that energy from the Sun is indirectly feeding the turtle.

60 points! I am leaning toward C. Temperature

A student conducts an experiment to test how the temperature affects the amount of salt that can dissolve in water. In the experiment, she uses 150 milliliters of water in each trial and stirs for five minutes each time.

What is the independent variable in this experiment?

the amount of salt

the time stirred

the temperature of the water

the amount of water

Answers

Answer:

C. Temperature of the water.

Explanation:

An independent variable is defined as the variable which is not affected by any other variable in the experiment while also being the variable that is changed and controlled by only the student.

All other stated variables are constant variables, which remain completely unchanged throughout the experiment, in this case the time stirred and the amount of salt, and amount of water.

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