chemistry 2

In the reaction 2Mg + O2 --> 2MgO, we have 48 total grams of Magnesium (2Mg) and 32 grams of Oxygen (O2). How many grams of Magnesium Oxide (2MgO) do we make if the reaction goes to completion?

80 g

In the reaction 2Mg + O2 --> 2MgO, the reactant(s) are

2Mg + O2

Iron is an example of a(n):

element

Density is a(n):

Intrinsic Property

In the oxidation reaction (rusting) iron plus oxygen becomes iron oxide:

Iron is a reactant

Water freezes at 0oC and boils at 100oC and Ethanol freezes at -117oC and boils as 78oC. If the temperature of the Ethanol and Water is 82oC, then:

We have a liquid and a gas.

Which of the following is not a chemical change? Mixing seawater with silver nitrate to make silver chloride. Burning magnesium in oxygen. Boiling liquid water to make gaseous steam. Combining hydrogen and oxygen gas to make water.

Boiling liquid water to make gaseous steam.

The element whose chemical symbol is "C" is:

Carbon

Which of the following is true concerning the laws of thermodynamics? Air pressure in car tires increases with falling temperatures. Heat death (no kinetic energy) for water molecules occur when water freezes at 0oC. Chemical and physical changes tend to make the universe more disorganized and random. As long as mass and energy are conserved, physical and chemical changes can take place in nature.

Chemical and physical changes tend to make the universe more disorganized and random.

In Chemistry, phase means:

A part of a sample with uniform composition and properties.

Homogenous mixtures

A physical blend of two or more components, having uniform composition where sampled.

Which of the following is an example of a physical, as opposed to chemical, change? A.Melting butter B.Toasting bread. C.Digesting a banana D.Cooking a hamburger

A. Melting butter

Which of the following is a physical property? Color Freezing Point Hardness All of the above.

All of the above.

What is meant by Conservation of Energy?

Any chemical or physical change does not create or destroy energy.

Which of the following is false about compounds and elements? All known elements are described in the periodic table. Compounds always contain more than two atoms. Elements and compounds contain atoms. The chemical behavior of the individual elements in a compound can be quite different than the compound.

Compounds always contain more than two atoms.

All of the following are general characteristics of a substance in the liquid state except: Ability to flow (fluid) Definite volume Definite shape Not easily compressed

Definite shape

Which is not a branch of chemistry?

Engineering Chemistry

Which of the following is not a state of matter? Plasma Solid Liquid Mixture

Mixture

The chemical symbol for the element Sodium is

Na

Distinguish between physical and chemical changes and give an example of each.

Physical change has to do with appearance and display of the object. In physical change the composition stays the same. In chemical change the composition of the substance changes. An example of a chemical change is burning wood. An example of a physical change is melting an ice cube.

A substance that can be separated into simpler substances only by chemical means:

compound