All categories

2 years ago

Is crumpling a sheet of paper a physical or chemical change? Why?

2 answers:

7 0

Crumpling a sheet of paper would be physical change. Only the appearance of the paper changes. The makeup of the paper is not being altered.

rjkz [21]2 years ago

3 0

Hi there!

Crumpling a piece of paper is a physical change.

Since there aren't any types of chemical reactions or chemical substance reactions when you crumple a piece of paper, it is a physical change.

Hope this helps!

You might be interested in

The human ear canal is about 2.3 cm long. If it is regarded as a tube open at one end and closed at the eardrum, what is the fun

mariarad [96]

Answer:

For the given conditions the fundamental frequency is 3728.26 Hertz

Explanation:

We know that for a pipe open at one end and closed at other end the fundamental frequency is given by

$f=\frac{V_{s}}{4L}$

where

f is the fundamental frequency

$V_{s}$ is the speed of sound in air in the surrounding conditions.

L = Length of the pipe

Applying values we get and using speed of sound as 343m/s we get

$f=\frac{343}{4\times 2.3\times 10^{-2}}=3728.26Hz$

7 0

2 years ago

Help Plsss

sattari [20]

On the Newtonian theory of gravity, gravitation affects anything with mass. Assuming that none of the answer choices is the only thing that exists in the universe, all of the answer choices are subject to the law of universal gravitation (hence “universal”).

Satellites, water, frogs, and stars all have mass as they are all composed of matter. Thus, all four answer choices should be circled.

3 0

3 years ago

A teacher told a learner to react benzene (CH) with chlorine (Cl₂) to

kolezko [41]

The minimum quantity of benzene, C₆H₆ needed for the reaction is 106.67 g

<h3>How to determine the theoretical yield of chlorobenzene, C₆H₅Cl</h3>

From the question given, the following data were obtained

Actual yield = 100 g
Percentage yield = 65%
Theoretical yield =?

Percentage yield = (Actual / Theoretical) × 100

65% = 100 / Theoretical

0.65 = Actual / Theoretical

Cross multiply

0.65 × Theoretical = 100

Divide both sides by 0.65

Theoretical = 100 / 0.65

Theoretical yield = 153.85 g

<h3>How to determine the mass of benzene, C₆H₆ needed</h3>

Balanced equation

C₆H₆ + Cl₂ → C₆H₅Cl + HCl

Molar mass of C₆H₆ = 78 g/mol

Mass of C₆H₆ from the balanced equation = 1 × 78 = 78 g

Molar mass of C₆H₅Cl = 112.5 g

Mass of C₆H₅Cl from the balanced equation = 1 × 112.5 = 112.5 g

SUMMARY

From the balanced equation above,

112.5 g of C₆H₅Cl were obtained from 78 g of C₆H₆

Therefore,

153.85 g of C₆H₅Cl will be produced from = (153.85 × 78) / 112.5 = 106.67 g of C₆H₆

Thus, the minimum amount of benzene, C₆H₆ needed for the reaction is 106.67 g

Learn more about stoichiometry:

brainly.com/question/16735180

#SPJ1

3 0

1 year ago

The magnetic field at the equator points north. If you throw a positively charged object (for example, a baseball with some elec

PilotLPTM [1.2K]

Answer:

The magnetic force points in the positive z-direction, which corresponds to the upward direction.

Option 2 is correct, the force points in the upwards direction.

Explanation:

The magnetic force on any charge is given as the cross product of qv and B

F = qv × B

where q = charge on the ball thrown = +q (Since it is positively charged)

v = velocity of the charged ball = (+vî) (velocity is in the eastern direction)

B = Magnetic field = (+Bj) (Magnetic field is in the northern direction; pointing forward)

F = qv × B = (+qvî) × (Bj)

F =

| î j k |

| qv 0 0|

| 0 B 0

F = i(0 - 0) - j(0 - 0) + k(qvB - 0)

F = (qvB)k N

The force is in the z-direction.

We could also use the right hand rule; if we point the index finger east (direction of the velocity), the middle finger northwards (direction of the magnetic field), the thumb points in the upward direction (direction of the magnetic force). Hence, the magnetic force is acting upwards, in the positive z-direction too.

Hope this Helps!!!

5 0

2 years ago

A machine is currently set to a feed rate of 5.921 inches per minute (IPM). Te machinist changes this setting to 6.088 IPM. By h

lukranit [14]

Answer:

By 16.7% or 0.167 IPM

Explanation:

Substracting the final IPM (6.088) to the initial IPM (5.921) gives us the net difference, which is how much did it increase in IPM. Multiplying this number by 100 gives us the percentual increase in the feed rate.

4 0

2 years ago

Read 2 more answers