changing substances

changes

100

when an object changes its state of matter (solid, liquid and gas)

what does a physical change do?

200

fizzing, bubbling, color changing, temperature changing, scent occurring & matter appearing inside a substance

give an example of a physical change (only 1)

300

a physical change can be restored (reversible) while a chemical change is permanent (irreversible) 

what is the most noticeable difference between a chemical or physical change?

400

false

true or false: physical changes are indicated by a decrease in temperature

500

answer has to be about an object changing its volume by getting crushed then getting mixed into another substance

give an example for when a physical change can be converted into a chemical change

conservation of mass

100

water

what does hydrogen and oxygen make?

200

the principle by which a physical quantity remains constant in a system

what does conservation mean? (scientific ver.)

300

total mass of products = total mass of reactants

what is the rule of the conservation of mass?

400

59g carbon dioxite

if 25 grams of carbon gets mixed with 34 grams of oxygen, how much grams of carbon dioxide is made?

500

reactants:

4 hydrogen, 2 oxygen

products:

4 hydrogen, 2 oxygen

it is balanced

is the following equation balanced:

2H₂ + O₂ -> 2H₂O

multiplying elements?

100

a subscript

what shows how much atoms there are in one element?

200

the co-efficient

what multiplies all the atoms in an element?

300

true

true or false: the atoms are only re-arranged in the product

400

both reactants and products have the same amount of atoms

what does it mean if an equation is balanced?

500

balanced

is the following equation balanced or unabalanced?

2Fe + 6HC2H3O2 → 2Fe(C2H3O2)3 + 3H₂

oxidation and reduction

100

the gain of oxygen

what is oxidation

200

rusting, rotting, combustion etc.

what is an example of oxidation?

300

reduction 

is this reduction or oxidation?

CuO+2H->Cu+H2O

400

magnesium (mg)

what element is being oxidized in the equation?

Mg+CuO->MgO+Cu

500

yes, it can be reversed

can oxidation be reversed?

burning magnesium

100

burning magnesium is an oxidation reaction

is burning magnesium oxidation or reduction?

200

magnesium oxide (MgO)

what is the product of magnesium and oxygen?

300

balance/scale

what is the piece of apparatus used to measure mass?

400

false 

true or false: magnesium has mass but oxygen does not due to being a gas.

500

intense brightness, radiation from UV and heat.

why is it dangerous to look at burning magnesium?