Question

physical and chemical changes homework

1. which statement describes a chemical property of the element magnesium?

a) magnesium is malleable.
b) magnesium conducts electricity.
c) magnesium reacts with an acid.
d) magnesium has a high boiling point.

1. two grams of potassium chloride are completely dissolved in a sample of water in a beaker. this solution is classified as

a) an element
b) a compound
c) a homogeneous mixture
d) a heterogeneous mixture

1. solid zinc chloride and liquid zinc chloride have different

a) empirical formulas
b) formula masses
c) ion ratios
d) physical properties

1. which statement describes a chemical property of oxygen?

a) oxygen has a melting point of 55 k.
b) oxygen can combine with a metal to produce a compound.
c) oxygen gas is slightly soluble in water.
d) oxygen gas can be compressed.

1. which set of procedures and observations indicates a chemical change?

a) ethanol is added to an empty beaker and the ethanol eventually disappears.
b) a solid is gently heated in a crucible and the solid slowly turns to liquid.
c) large crystals are crushed with a mortar and pestle and become powder.
d) a cool, shiny metal is added to water in a beaker and rapid bubbling occurs.

1. given the equation: i₂(gas)→i₂(liquid)

which phrase describes this change?
a) chemical change, energy absorbed
b) physical change, energy absorbed
c) chemical change, energy released
d) physical change, energy released

1. which set of procedures and observations indicates a physical phase change?

a) ethanol is added to an empty beaker and the ethanol eventually disappears.
b) a solid is gently heated in a crucible explodes.
c) large crystals are crushed with a mortar and pestle and become powder.
d) a cool, shiny metal is added to water in a beaker and rapid bubbling occurs.

1. which process is a chemical change?

a) melting of ice
b) boiling of water
c) subliming of ice
d) decomposing of water

1. which two substances can not be broken down by chemical change?

a) c and cuo
b) c and cu
c) co2 and cuo
d) co2 and cu

1. which of the following will result in the formation of a new substance?

a) burning
b) cutting a piece of paper
c) melting ice
d) melting candle wax

1. which process represents a chemical change?

a) melting of ice
b) corrosion of copper
c) evaporation of water
d) crystallization of sugar

1. given the balanced particle - diagram equation:

particle - diagram showing two different types of atoms combining to form a compound
which statement describes the type of change and the chemical properties of the product and reactants?
a) the equation represents a physical change, with the product and reactants having different chemical properties.
b) the equation represents a physical change, with the product and reactants having identical chemical properties.
c) the equation represents a chemical change, with the product and reactants having different chemical properties.
d) the equation represents a chemical change, with the product and reactants having identical chemical properties.

Explanation:

Answer:

(1) C. Magnesium reacts with an acid.
(2) C. a homogeneous mixture
(3) D. physical properties
(4) B. Oxygen can combine with a metal to produce a compound.
(5) D. A cool, shiny metal is added to water in a beaker and rapid bubbling occurs.
(6) D. Physical change, energy released
(8) A. Ethanol is added to an empty beaker and the ethanol eventually disappears.
(9) D. decomposing of water
(10) B. C and Cu
(11) A. Burning
(12) B. corrosion of copper
(13) C. The equation represents a chemical change, with the product and reactants having different chemical properties.