lesson 2- Early chemistry + Atomic models

Question 1

can heating food sterilize food for the long term or temporarily?

Answer 1

heating food only temporarily sterilizes food

Question 2

what does freezing food prevent?

Answer 2

Microbial Growth

Question 3

Salting: A physical change or chemical change? What is it meant for?

Answer 3

A physical change, meant to preserve meat and fish. It draws water out of is.

Question 4

Fermentation: A physical change or a chemical change? What is it meant for?

Answer 4

Using the lactobacilli bacteria, it converts starches and sugars into lactic acid. This prevents bacterial growth. (no rotting food yippee!)

Question 5

metallurgy

Answer 5

the science of producing and using metals (eg. harpoon head used for hunting made out of iron)

Question 6

The five metals known in ancient times

Answer 6

1. Gold
2. Copper
3. Silver
4. Lead
5. Iron

Question 7

is native copper only found in small amounts? What about compounds with other elements? How is it seperated?

Answer 7

Yes and by smelting

Question 8

smelting

Answer 8

seperating a metal from other elements in a compound by melting

Question 9

How was bronze made in the Bronze age

Answer 9

it was made by smelting COPPER ore with TIN ores, making it a stronger tool to be used

Question 10

what elements does steel come from?

Answer 10

Iron and Carbon

Question 11

The 4 Atomic models form the

Answer 11

building blocks of ALL matter

Question 12

Dalton atomic model

Answer 12

the billiard ball model in which atoms of different elements vary in size, mass, and chemical behavior

Question 13

Thomson

Answer 13

plum pudding model, atoms are positively charged with negative charges embedded in the postive ball. (think of a plum pudding, the plum is the negative part of the model because its the most undesirable, while the pudding is the positve part of the model because it is most desired)

Question 14

Rutherford

Answer 14

Atom contains a positively charged core called the nucleus. Negative charges surround the nucleus. (GOLD FOIL EXPERIMENT determined that the atom is mostly empty space with a tiny positively charges nucleus)

Question 15

Bohr

Answer 15

the solar system model, in which protons are all in the nucleus while electrons move around the nucleus in definite orbits.

Question 16

De Broglie & Schrodinger

Answer 16

Quantum wave model believed that the electron forms a cloud around the nucleus.