Unit 1

Question 1

what is an element?

Answer 1

any substance that cannot be decomposed into simpler substances by ordinary chemical processes (identical atoms)

Question 2

What is a compound?

Answer 2

a substance made up of two or more different chemical elements

Question 3

What is a pure substance?

Answer 3

an element or compound made up of one type of particle

Question 4

What is a mixture?

Answer 4

a material made up of two or more different chemical substances which are not chemically bonded

Question 5

what is heterogeneous?

Answer 5

mixtures that have visually distinguishable components

Question 6

what is homogeneous?

Answer 6

appears uniform throughout

Question 7

Define Atomic Number

Answer 7

The number of protons in the nucleus (charge)

Question 8

Define Mass Number

Answer 8

The number of protons and neutrons in an atom (mass number = protons + neutrons.)

Question 9

Define Isotope

Answer 9

Atoms that have different numbers of neutrons

Question 10

What is the “Period Law” ?

Answer 10

elements that are arranged in order of increasing atomic number

Question 11

Where are metals in the periodic table?

Answer 11

Metals are located on the left of the periodic table (separated by staircase)

Question 12

Where are nonmetals in the period table?

Answer 12

nonmetals are located on the upper right. (separated by staircase)

Question 13

What types of elements form ionic compounds?

Answer 13

Ionic compounds are (usually) formed when a metal reacts with a nonmetal (or a polyatomic ion)

Question 14

What types form covalent compounds?

Answer 14

Covalent compounds are formed when two nonmetals react with each other

Question 15

which was does atomic radius decrease?

Answer 15

Left to right

Question 16

which way does atomic radius increase?

Answer 16

Top to Bottom

Question 17

why does the atomic radius decrease left to right?

Answer 17

the more electrons in the outer energy level means there will be a greater attraction between the outer energy level and the nucleus

Question 18

Why does the atomic radius increase top to bottom?

Answer 18

Each new period means another energy level, which means a larger atom

Question 19

What is ionization energy

Answer 19

the amount of energy required to remove an electron from an isolated atom or molecule

Question 20

Which has more ionization energy?
Non metals or Metals?

Answer 20

I.E. of non metals are generally higher than I.E. of metals

Question 21

which way does Ionization energy increase

Answer 21

left to right in a period

Question 22

why does the Ionization energy increase Left to right?

Answer 22

the decrease in atomic size

Question 23

which way does ionization energy decrease?

Answer 23

down a group

Question 24

Why does Ionization energy decrease top to bottom

Answer 24

increase in atomic size