Unit test 1

Question 1

Formula of Zinc Chloride

Answer 1

ZnCl2

Question 2

Alloy definition

Answer 2

A solid that is a mixture of 2 or more ELEMENTS.

Question 3

Is an alloy heterogenous or homogenous?

Answer 3

Homogenous

Because alloys appear to be uniform. Chemical composition is pretty even throughout.

Question 4

What part of the Gold Foil experiment did we make an alloy of copper and zinc?

Answer 4

When we placed the penny with the zinc coating directly on the hot plate. When it turned gold.

Question 5

Name of alloy that you produced between copper and zinc?

Answer 5

Brass

Question 6

Did the mass of the penny increase or decrease after it turns silver?

Answer 6

Increase- because a zinc coating was added to the penny

Question 7

Would the Mass of silver penny increase or decrease when it turned gold?

Answer 7

The mass would stay the same because we aren’t taking any atoms away.
(Adding more atoms=more mass)

Question 8

True or False: “The copper atoms in the original penny turn into gold atoms by the end of the experiment”

Answer 8

The copper atoms mixed with the zinc atoms

Question 9

Why is steel preferred over just using pure elemental iron?

Answer 9

1. Doesn’t rust as easily
2. More flexible
3. Lighter
4. Stronger (less brittle)

Question 10

What did Ernest Rutherford discover?

Answer 10

He discovered that alpha particles passed through (mostly empty space)

Question 11

How do u calculate density?

Answer 11

Mass divided by volune

Question 12

What’s the density of water?

Answer 12

1.0 g/cm3

Question 13

A
X
Z

What does each letter mean?

Answer 13

A=number of protons and neutrons
Z=number of the protons
X=element

Question 14

Definition: ion

Answer 14

When the atom has a charge (can be positive or negative). This is determined by the number of electrons.

Question 15

What’s an isotope?

Answer 15

When there is an imbalance of protons and neutrons. Determined by the number of neutrons.

Question 16

What’s the mass number?

Answer 16

The number of protons and neutrons.

Question 17

What’s atomic mass?

Answer 17

The total mass of particles of matter in an atom

Question 18

What’s an alkali metal?

Answer 18

Any of the six chemical elements that make up Group 1 of the periodic table. They have one valence electron. Very reactive and are soft, shiny metals.

Question 19

Noble gases

Answer 19

Is not that reactive. They have 8 valence electrons. Group 18

Question 20

Nonmetal:

Answer 20

Not a metal. Form anions. Brittle and low melting point and are poor conductors

Question 21

A period:

Answer 21

Is a row of chemical elements (ACROSS)

Question 22

Combustion:

Answer 22

The process of burning something

Question 23

Atomic number:

Answer 23

Number of protons

Question 24

Octet rule

Answer 24

All elements try to combine with other elements by sharing or transferring electrons to fill their outer energy levels

Question 25

Parts of an atom

Answer 25

Electrons protons and neutrons

Question 26

Transition metals:

Answer 26

Elements that have valence electrons in two shells instead of only one. Great conductors of heat as well as electricity. Very malleable

Question 27

Alkali Earth metals:

Answer 27

Have two valence electrons. Highly reactive and NOT naturally found in their elemental state. Group 2.

Question 28

Law of conservation of matter:

Answer 28

Matter is neither created nor destroyed.

Question 29

Cation

Answer 29

Positively charged ion

Question 30

Element:

Answer 30

A SUBSTANCE that cannot be broken down into simpler substances

Question 31

Compound

Answer 31

Made of two or more elements that were mixed CHEMICALLY

Question 32

Mixture

Answer 32

Substances formed by PHYSICALLY mixing two or more substances

Question 33

What is the gold foil experiment

Answer 33

Conducted by Ernest Rutherford. He used a thin lead tube to shoot positively charged particles (alpha particles) at a very thin sheet of gold foil.

Question 34

Metal:

Answer 34

Has high conductivity. Malleable. High reflectivity of light

Question 35

Anion

Answer 35

ION with a negative charge. More electrons

Question 36

Groups/families:

Answer 36

Groups of elements with similar properties.
Ex: alkali metals, transition metals, halogens

Question 37

Halogens:

Answer 37

A chemical element that forms a salt when reacting with a metal. 7 valence electrons.

Question 38

How to calculate (weighted) average atomic mass?

Answer 38

(% abundance/100)(mass of isotope #1) + (% abundance/100)(mass of isotope #2)

Question 39

What is a result of burning the candle?

Answer 39

H20, co2 and energy

Question 40

What is needed to brun the candle

Answer 40

Fuel(candle wax) and oxygen and a spark from the match?

Question 41

What we’re the chemical changes in the candle lab?

Answer 41

1. When u blow into the line solution and mix it because you are utilizing a chemical and mixing it with something else
2. Wax burning

Question 42

What we’re some physical changes in the candle lab?

Answer 42

When the wax MELTS because it’s transitioning from solid to gas without using chemicals

Question 43

What does AMU stand for

Answer 43

Atomic mass unit

Question 44

What’s the difference between atomic mass and mass number

Answer 44

Mass number is the total number of protons and neutrons in one particular isotope. Atomic mass is the WEIGHTED average of all isotopes of that element that are naturally found on earth.