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Flashcards in Unit 2 - Chemistry Deck (35):
1

Which scientist discovered that all atoms of an element are the same and they cannot be created or destroyed?

Dalton

2

Which scientist proposed that an atom is the smallest piece any substance can be separated into?

Democritus

3

Which scientist discovered the nucleus and the proton?

Rutherford

4

Which scientist discovered that atoms contain negatively charged electrons floating in a positively charged sphere?

Thompson

5

Which scientist proposed that electrons are found in orbits?

Bohr

6

Name the first 20 elements in order.

Hydrogen, helium, lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, neon, sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, argon, potassium, calcium

7

List 2 defining properties for Alkali Metals.

Silver, very reactive

8

List 2 defining properties for Alkaline Earth Metals.

Silvery-white, shiny

9

List 2 defining properties for Halogens.

7 valence electrons, reactive non-metals

10

List 2 defining properties for The Noble Gases.

Odorless, low chemical reactivity

11

What is the formula for density?

D=M/V

12

Using the particle theory of matter, explain how a substance changes from a liquid to a gas.

When particles heat up. Since particles are always moving, when it is heated up they move faster and farther apart.

13

What is in the Particle Theory of Matter?

All matter is made up of particles, the type of particle makes the substance what it is, particles are always moving, the faster they move- the further apart they get, there are forces of attraction between particles.

14

What is the difference between an element and an ion?

Electrons don't equal protons - ION, elements do

15

Why is the compound H2O stable while the elements H and O are not?

Sharing electrons to fill shell

16

What is the difference between NH3 and AlF3?

Covalent vs Molecular

17

Define "covalent".

Sharing of electrons

18

Define "molecular".

Two or more atoms held together by molecular bonds.

19

You are conducting a lab where you mix a white powder with an acid. Oxygen or Carbon Dioxide or Hydrogen gas is produced. What would you observe that would confirm that a gas is being produced.

Formation of bubbles.

20

Two jars filled with white powder have lost their labels. One contains starch and the other contains baking soda. What 2 chemical properties and physical properties could you use to tell the difference between those two powders?

Starch chemical properties- Flammable
Starch physical properties- insoluble in cold water or alcohol, higher melting point
Baking Soda chemical properties- soluble in water, lower melting point
Baking Soda physical properties- Not flammable, neutralize battery and acid corrosion

21

List the Alkali Metals

Hydrogen, Lithium, Sodium, Potassium (first column)

22

List the Alkaline Earth Metals

Beryllium, Magnesium, Calcium (second column)

23

List the Halogens

Fluorine, Chlorine (seventh column)

24

List The Noble Gases

Helium, Neon, Argon

25

Define "ionic bonds"

Metal + non-metal, transfer of electrons

26

Define "molecular bonds"

2+ non-metals (HOBrFINCl) share electrons

27

How do you solve for protons?

Atomic number

28

How do you solve for neutrons?

Atomic mass-atomic number

29

Can a pure substance contain two or more types of particles?

No, that is a mixture.

30

Define "solution"

A mixture (solid, liquid, gaseous) made up of only one visible component

31

What is a physical property?

Characteristics determined w/o changing the substance. Reversible

32

What is a chemical property?

Characteristics observed when the composition of a substance is changed (aka a chemical reaction). Irreversible

33

Give examples of physical property.

Colour, malleability, aroma, taste, boiling point, melting point

34

Give examples of chemical property.

New substance, fizzes, change of state, precipitation

35

State the "Stable Octet Rule".

A chemical rule of thumb that reflects observation that atoms of main-group elements tend to combine in such a way that each atom has eight electrons in its valence shell, giving it the same electron configuration as a noble gas