Please help this affects my grade a lot and im confused Double Replacement/Combustion I need to find the product of each one
zinc oxide + Cobalt(III) nitrite
Calcium hydroxide + phosphoric acid
Copper(I) dichromate + Iron(III) arsenate
Hydrochloric acid + aluminum hydroxide

1 ) Cobalt(II) nitrate react with nitrate zinc(II) to produce cobalt(III)-zinc oxide, nitrogen dioxide and oxygen  

2Co(NO3)2 + Zn(NO3)2 → Co2ZnO4 + 6NO2 + O2

2) Calcium hydroxide react with phosphoric acid to produce calcium, hydrogen phosphate and water

Ca(OH)2 + H3PO4 → CaHPO4 + 2H2O

3) Copper(II) dichromate will react with Iron(III) arsenate to form Copper(II) Arsenate and Iron(III) dichromate

3Cr2CuO7 + 2AsFeO4 → Cu3(AsO4)2 + Fe2(Cr2O7)3

Reaction Type : Double Displacement

4) aluminium hydroxide and hydrochloric acid react to form aluminium chloride and water

Al(OH)3 + 3HCl → AlCl3 + 3H2O

b) mutualism

hope this : )

the ideal gas law equation is as follows

pv = nrt

where p - pressure

v - volume

n - number of moles

r - universal gas constant

t - temperature

so if the pressure, volume and temperature are already known

we are left with n and r

since r is the universal gas constant that has a known fixed value then r too is known

so we are left with 'n'

once we know temperature volume and pressure

we can find the number of moles of gas present using the ideal gas law equation

this is not my own answer, this is an answer for the same question by the user blahblahmali. i do not claim ownership of this account.