1D.1,2 empirical formula and molecular formula

Question 1

what are the empirical formulae

Answer 1

the smallest whole number ratios of atoms of each element in a compound

Question 2

how can we reduce copper oxide

Answer 2

1. add copper oxide to a tube
2. then heat the copper oxide in a stream of hydrogen gas
3. the oxygen would react with the stream of hydrogen forming a steam
4. the colour of the solid would gradually turn orange-brown (the colour of copper)
5. burn the excess gases for safety reasons
6. after cooling dry, then weigh the copper
7. repeat the experiment till the mass doesn’t change

Question 3

what compounds have the same empirical and molecular formulae

Answer 3

H2O and CO2

Question 4

what are molecular formulae

Answer 4

it is the actual number of atoms of each element in a compound

Question 5

what is the ideal gas equation used for

Answer 5

it is used for gases or volatile liquids that are above their boiling points to find the amount of substance in moles

Question 6

what are the SI units for the ideal gas equations

Answer 6

P= pressure in Pa 
v= volume in m^3
T= tempreture in kalvien 
n= number of moles 
R= the gas constant

Question 7

what is the value of the gas constent

Answer 7

8.31 mol^-1 K^-1

Question 8

how to change from KPa to Pa

Answer 8

multiply by 10^3

Question 9

how to change from m^3 to cm^3

Answer 9

10^6

Question 10

how to change for c to K

Answer 10

by adding 273