It depends if it occurs naturally it has oxidation number of 0
but when it react with other element it has an oxidation number of -1
The energy change if 84.0 g of CaO react with excess water is 98KJ of heat is released.
calculation
heat = number of moles x delta H
delta H = - 65.2 Kj/mol
first find the number of moles of CaO reacted
moles = mass/molar mass
the molar mass of CaO = 40 + 16= 56 g/mol
mass = 84 g
moles therefore = 84 g/56 g/mol =1.5 moles
Heat is therefore = 1.5 moles x -65.2 = - 97.8 Kj = -98 Kj
since sign is negative the energy is released
Answer:
c
Explanation:
I think it is right not sure but hope it helped
first of all there is only two types of selective breeding and they are hybridization and inbreeding.
Answer:
At -13 
, the gas would occupy 1.30L at 210.0 kPa.
Explanation:
Let's assume the gas behaves ideally.
As amount of gas remains constant in both state therefore in accordance with combined gas law for an ideal gas-
where 
and 
are initial and final pressure respectively.
and 
are initial and final volume respectively.
and 
are initial and final temperature in kelvin scale respectively.
Here 
, 
, 
, 
and 
Hence 
So at -13 , the gas would occupy 1.30L at 210.0 kPa.
