Question

Question 21
Classify each change listed below as either a chemical or physical change in matter.

Column A
1.
Liquid water boiling and becoming steam:
Liquid water boiling and becoming steam
2.
Silver metal tarnishing and becoming silver sulfide.:
Silver metal tarnishing and becoming silver sulfide.
3.
Paper burning:
Paper burning
4.
Bending copper wire:
Bending copper wire
5.
Dissloving salt in water:
Dissloving salt in water
6.
Iron rusting to become iron oxide.:
Iron rusting to become iron oxide.
Column B
a.Chemical Change
b.Physical Change
Question 22
What would happen if a scuba tank (a rigid, sealed gas cylinder) heats up?

a
The size of the gas particles in the tank would increase.
b
The pressure exerted by the gas in the tank would increase.
c
The number of particles in the tank would increase.
d
The density of the gas in the tank would increase.
Question 23
What is the difference between a vector and a scalar?

a
A vector measurement contains a direction and magnitude, a scalar measurement only contains a magnitude
b
A vector measurement is required for distance, a scalar measurement is required for displacement
c
A vector is only used in measuring forces, a scalar is only used in measuring mass
d
A vector is only measured in SI units, where scalars are only measured in US Customary units

Answer 1

**Question 21: Classification of Changes**
1. Liquid water boiling and becoming steam: **b. Physical Change**
2. Silver metal tarnishing and becoming silver sulfide: **a. Chemical Change**
3. Paper burning: **a. Chemical Change**
4. Bending copper wire: **b. Physical Change**
5. Dissolving salt in water: **b. Physical Change**
6. Iron rusting to become iron oxide: **a. Chemical Change**

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**Question 22: Effect of Heating a Scuba Tank**
The correct answer is: **b. The pressure exerted by the gas in the tank would increase.**
When the temperature of the gas increases, the kinetic energy of the gas particles increases, leading to an increase in pressure, as long as the volume remains constant.

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**Question 23: Difference Between Vector and Scalar**
The correct answer is: **a. A vector measurement contains a direction and magnitude, a scalar measurement only contains a magnitude.**
Vectors have both magnitude and direction (e.g., velocity, force), while scalars have only magnitude (e.g., temperature, mass).