Stoichmetric Relationships

Question 1

Elements

Answer 1

Elements are single substances, composed of atoms of the same type

Question 2

Compounds

Answer 2

Compounds contain a fixed ration of atoms of different elements and have different properties from their compound elements

Question 3

Kinetic - Molecular Theory

Answer 3

Describes the differences in the properties of solids, liquids and gases on the basis of the different kinetic energies of the particles.

Question 4

The relative atomic mass (AR)

Answer 4

The relative atomic mass of an element is the average mass of an atom according to relative abundance’s of its isotopes, on a scale where the mass of one atom of 12 is 12 exactly. It has no units.

Question 5

The relative molecular mass (MR)

Answer 5

The relative molecular mass is the sum of the relative atomic masses of the atoms in the molecular formula.

Question 6

Percentage Yield

Answer 6

Percentage yield = (experimental yield / theoretical yield) x100%

Question 7

Empirical formula

Answer 7

The empirical formula of a compound is the simplest whole number ratio of the atoms it contains

Question 8

Molecular Formula

Answer 8

The molecular formula of a compound is the actual number of atoms of each element present

Question 9

Solute

Answer 9

The solute is the substance dissolved in the solvent in forming a solution

Question 10

Solvent

Answer 10

The solvent is the liquid that dissolved another substance or substances to form a solution

Question 11

Solution

Answer 11

A solution is a homogenous mixture of a liquid with another substance

Question 12

Concentration

Answer 12

Concentration is the amount of solute in a known volume of solution

Question 13

Absolute zero

Answer 13

The temperature at which everything would be in its lowest energy state -273oC

Question 14

Avogadro’s law

Answer 14

Equal volumes of ideal gases measured at the same temperature and pressure contain the same number of molecules

Question 15

Heterogeneous Mixture

Answer 15

Is a mixture that does not have a uniform composition and consists of separate phases; can be separated by mechanical means

Question 16

Homogeneous Mixture

Answer 16

Is a mixture that has the same (uniform) composition throughout the mixture and consists of only one phase

Question 17

Ideal gas

Answer 17

A theoretical model that approximates the behavior of real gases: it can be defined in terms of macroscopic

Question 18

Precision

Answer 18

It relates to the reproducibility of results; if a series of readings is taken with high precision