Test week 10

Question 0

list the evidence that an chemical change has occurred

Answer 0

change of colour
seeing bubbles 
smelling gas
seeing a new solid 
observing energy that is absorbed in the form of heat  or light

Question 1

what is the difference between physical and chemical change

Answer 1

physical is when nothing new is created, chemical is where something new is created

Question 2

list the properties of metal

Answer 2

shiny 
solid at room temp
good for conducting heat + electricity
malleable 
ductile

Question 3

properties of a non metal

Answer 3

dull
do not conduct heat and electricity
brittle

Question 4

what is a compound

Answer 4

a compound is made up of more than one type of atom

Question 5

what is a molecule

Answer 5

when two or more atoms join

Question 6

what are elements

Answer 6

a substance mad up of purely 1 type of atom

Question 7

define corrosion

Answer 7

the process of a solid being altered by a chemical reaction

Question 8

define rust

Answer 8

rust is a reddish coating of iron oxide that forms around iron or steel when it is exposed to moisture or air.

Question 9

what is the word equation for rusting

Answer 9

metal + oxygen + water - metal oxide

Question 10

how many atoms are in C2H6

Answer 10

Carbon 2

Hydrogen 6

Question 11

how many atoms are there in NaCl

Answer 11

Sodium 1

Chlorine 1

Question 12

how many atoms are there in Mn2O7

Answer 12

magnesium 2

Oxygen 7

Question 13

write the word equation for sodium reacting with chlorine and creating sodium chloride

Answer 13

sodium + chlorine - sodium chloride

Question 14

write the word equation for iron reacting with sulfur to produce iron sulfide

Answer 14

iron + sulfur - iron sulfide