Q: A sample of water is heated from 20°C to 80°C. If the mass of water is 50 g and the specific heat capacity is $$4.18\ \text{J/g} \cdot \text{°C}$$, how much energy is required? (Use $$q = m \times c \times \Delta T)$$

$$q = 50 \times 4.18 \times (80 - 20) = 12,540\ \text{J}$$

Question 1

Which of the following best describes a compound?

Accepted Answer

A substance made of two or more elements chemically bonded together.

Question 2

A student mixes sand and salt in water. After stirring, the sand settles at the bottom while the salt dissolves. What type of mixture is this?

Accepted Answer

Heterogeneous mixture

Question 3

Which process would best separate a mixture of two liquids with different boiling points?

Accepted Answer

Distillation

Question 4

Which of the following is an example of a physical change?

Accepted Answer

Melting ice

Question 5

According to the law of conservation of mass, what happens to the mass of reactants and products in a chemical reaction?

Accepted Answer

The total mass remains constant; mass is neither created nor destroyed.

Question 6

Which of the following best describes an exothermic reaction?

Accepted Answer

A reaction that releases energy to its surroundings.

Question 7

A sample of water is heated from 20°C to 80°C. If the mass of water is 50 g and the specific heat capacity is $$4.18\ 	ext{J/g} \cdot 	ext{°C}$$, how much energy is required? (Use $$q = m 	imes c 	imes \Delta T)$$

Accepted Answer

$$q = 50 	imes 4.18 	imes (80 - 20) = 12,540\ 	ext{J}$$

Question 8

Which statement correctly distinguishes between crystalline and amorphous solids?

Accepted Answer

Crystalline solids have long-range repeating order, while amorphous solids lack such order.

Question 9

Which of the following is NOT a physical property?

Accepted Answer

Reactivity with acid

Question 10

A gas is compressed in a cylinder. Which property of gases does this demonstrate?

Accepted Answer

Gases are compressible.

Question 11

Which of the following best describes potential energy in a chemical system?

Accepted Answer

Energy due to the position and composition of particles.

Question 12

A mixture of oil and water is poured through filter paper. What separation technique is being used?

Accepted Answer

Filtration

Question 13

Which of the following is a chemical property?

Accepted Answer

Ability to rust

Question 14

Which of the following statements about energy is correct?

Accepted Answer

Energy is the capacity to do work.

Question 15

A chemical reaction absorbs heat from the surroundings. Which term describes this process?

Accepted Answer

Endothermic

Question 16

Which temperature scale is based on absolute zero and avoids negative values?

Accepted Answer

Kelvin

Question 17

Which of the following is a unit of energy commonly used in measuring household electricity consumption?

Accepted Answer

Kilowatt hour

Question 18

If 1 big calorie is equivalent to 1000 little calories, how much energy is required to raise the temperature of 1 kg of water by 1°C?

Accepted Answer

1000 little calories

Question 19

Which of the following best describes a homogeneous mixture?

Accepted Answer

A mixture where components are mixed so well they appear as one substance.

Question 20

A student wants to separate a mixture of sand and salt dissolved in water. Which sequence of techniques should they use?

Accepted Answer

Filtration to remove sand, then distillation to recover salt from water.

Matter, States, Properties, and Energy in Chemistry

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드