Physical Science: Chapter 2 Study Guide

List 4 ways to detect that a chemical change has occurred.

-change of color -bubbling/fizzing -exploding -density

Physical properties

-color -density -magnetism -melting point -conducting electricity -boiling point

Chemical properties

-dissolving -reactivity -corrosion -flammability

Explain why elements and compounds are pure substances.

A compound can be destroyed and composed of two or more different atoms

Explain the different between a pure substance and a homogeneous mixture.

A pure substance is a element or compound. A homogeneous mixture has the same proportions.

Describe how the characteristic properties of a piece of ice are different from its other properties.

Becomes liquid, water or gas or water vapor

Explain how aluminum is a suitable material to use in making cans based on its physical and chemical properties.

It is very malleable and very flexible. It is also waterproof, and non reactant.

When the water is mixed with rubbing alcohol, the two liquids completely dissolve. Are the two liquids miscible, or they immiscible? Explain the difference between the two terms.

They are miscible because miscible is being mixed together and immiscible is making layers.

Compare physical changes and chemical changes.

They both change the physical properties of a substance.

When sugar is added to water, the sugar dissolves and the resulting liquid is clear. Do the sugar and water from a pure substance, or do they form a mixture? Explain your answer.

They form a mixture because the water is sweet now.

When wood is burned, new substance are produced, Describe this reaction, and explain what type of change occurs. Use the terms flammability, chemical property, physical change or chemical change.

When wood burns it has a physical change when it turns into ash. It also changes the chemical property when there is ash in the air. The flammability changes when the ashes run out.

Explain why baking is a chemical change.

You are creating a new substance. You cant change it back to its original state.

Explain why dissolving is a physical change.

You aren't burning it and it does back to its original state.

Physical change

a change of matter from one form to another without a change in chemical properties

Chemical change

a change that occurs when one or more substances change into entirely new substances with different properties

Mixture

a combination of two or more substances that are not chemically combined

Molecule

a group of atoms that are held together by chemical forces

a pail of sand and water is

a heterogeneous mixture

sea water is

a heterogeneous mixture

air is

a homogeneous mixture

banana split is

a homogeneous mixture

chocolate syrup is

a homogeneous mixture

human blood is

a homogeneous mixture

Which of the following is an example of a chemical change? gasoline evaporating sugar dissolving in water a metal surface rusting a mixture separating into its components

a metal surface rusting

Pure Substance

a sample of matter, either a single element or a single compound, that has definite chemical and physical properties

Compound

a substance made up of two or more different elements joined by chemical bonds

Element

a substance that cannot be separated or broken down into simpler substances

Compare and contrast atoms and molecules

an atom has one molecule and a molecule has more than on nucleus

Matter

anything that has mass and takes up space

What is matter?

anything that takes up space and has mass

Classify each of the following as a physical or chemical property of phosphorus: It burns in air

chemical

Classify each of the following as a physical or chemical property of sulfur: It combines with oxygen

chemical

Classify each of the following as a physical or chemical property of sulfur: It reacts with hydrogen to form a gas

chemical

chemical or physical change: burning propane

chemical

chemical or physical change: burning wood

chemical

chemical or physical change: cooking

chemical

Classify each of the following as an element or a compound: acetylene, C₂H₂

compound

Classify each of the following as an element or a compound: aspirin, C₉H₈O₄

compound

Classify each of the following as an element or a compound: benzene, C₆H₆

compound

Which of the following terms most accurately describes carbon dioxides? element compound mixture solution

compound

Compute the density of an 820 g sample of pure silicon occupying a 350 cm³ container.

d= m/v d= 820 g/ 350 cm³ d= 2.34 g/cm³

What is the formula for density?

d=m/v v=m/d m=d x v

Classify each of the following as an element or a compound: titanium, Ti

element

Classify each of the following as an element or a compound: zinc, Zn

element

Classify each of the following as an element or a compound: aluminum, Al

element

If you add oil to water and shake the liquid, you will form a

heterogenous mixture

Calculate the mass of a sample of pure silver (density = 10.49 g/cm³) that has a volume of 12.99 cm³

m=d x v m= 10.49 g/cm³ x 12.99 cm³ m= 136.2 g/cm

Which of the following is an example of a physical change? melting ice cubes burning paper rusting iron burning gasoline

melting ice cubes

Determine which of the following are pure substances and which are mixtures: an egg yolk

mixture

Determine which of the following are pure substances and which are mixtures: honey

mixture

Determine which of the following are pure substances and which are mixtures: salt water

mixture

Classify each of the following as a physical or chemical property of phosphorus: It has a density of 1.82 g/cm³

physical

Classify each of the following as a physical or chemical property of phosphorus: It is a white, waxy solid

physical

Classify each of the following as a physical or chemical property of phosphorus: Its boiling point is 280.3°C

physical

Classify each of the following as a physical or chemical property of phosphorus: Its melting point is 44.1°C

physical

Classify each of the following as a physical or chemical property of sulfur: It is a yellow solid

physical

Classify each of the following as a physical or chemical property of sulfur: Its density is 2.97 g/cm³

physical

Classify each of the following as a physical or chemical property of sulfur: Its melting point is 112°C

physical

chemical or physical change: bending a metal rod

physical

chemical or physical change: breaking glass

physical

chemical or physical change: painting wood

physical

Determine which of the following are pure substances and which are mixtures: ammonia, NH₃

pure substance

Determine which of the following are pure substances and which are mixtures: isopropyl alchohol, C₃H₈O

pure substance

Determine which of the following are pure substances and which are mixtures: mercury, Hg

pure substance

compounds and elements are

pure substances

which of the following is a pure substance? grape juice saltwater table salt gasoline

table salt

Reactivity

the capacity of a substance to combine chemically with another substance

The photograph shows magnesium burning in the presence of oxygen. Give some evidence that a chemical change is occurring.

the magnesium that is burning is changing color

Density

the ratio of the mass of a substance to the volume of the substance

Atom

the smallest unit of an element that maintains the chemical properties of that element

Boiling Point

the temperature and pressure at which a liquid becomes a gas

Which of the following is a mixture? air salt water sulfur

water