Carter - 1st 9wks Review

What happens to the temperature of a sample of matter as it changes from a liquid to a gas?

• temperature increases

• temperature decreases

• temperature remains constant

• temperature first decreases, and then increases

On a hot day, a puddle dries up. Which statement describing this event is true?

• The water in the puddle boils and becomes a gas.

• The water in the puddle evaporates into water vapor.

• The water in the puddle condenses and becomes part of the air.

• The water in the puddle changes into particles of oxygen in the air.

Chemical changes result in new substances, but physical changes do not. Which process is an example of a chemical change?

• chopping a tree

• cooking a steak

• heating a cup of tea

• drying clothes in the dryer

Which type of changes observe the law of conservation of mass?

• only changes of state

• only physical changes

• only chemical changes

• physical changes and chemical changes

A child is upset because his ice cream is melting. He thinks he now has less dessert. Which of the following explanations correctly states why the child is incorrect?

• He actually has more, not less, ice cream.

• No mass is lost during a change of state.

• The mass will increase if he freezes the melted ice cream.

Magnetism, solubility, and malleability are physical properties of matter. What makes these properties different from chemical properties?

• Physical properties relate to elements rather than compounds.

• Physical properties appear only after a chemical change occurs.

• Physical properties can be observed without attempting to change the identity of the substance.

• Physical properties describe elements in the solid state rather than in the liquid or gas state.

There are several differences between chemical and physical changes. Which process is an example of a chemical change?

• steam rising from a boiling pot of soup

• a metal railing rusting in damp weather

• alcohol evaporating from a cotton swab

• a piece of wood shrinking as it dries out.

When paper is burned, the mass of the remaining ash is less than the mass of the original paper. Which statement best explains this result?

• The ash has less volume than the paper.

• Some of the matter is destroyed during the reaction.

• The mass of the ash cannot be accurately determined.

• Some of the products of the reaction were given off as a gas.

In a neutral atom, the number of electrons equals the number of what other part?

• protons

• neutrons

• nuclei

• energy levels

A rock is dropped into a graduated cylinder filled with 35 mL of water. What is the volume of the rock? (Hint: 1 mL water = 1cm)

• 40 cm

• 14 cm

• 5 cm

• 35 cm