<span>The words you seek are soluble and insoluble.The chemical you want is an acid. Add an acid (acetic acid or hydrochloric acid) and the CaCO3 will fizz but CaCl2 will not</span>
As,
5471 kJ heat is given by = 1 mole of Octane
Then,
5310 kJ heat will be given by = X moles of Octane
Solving for X,
X = (5310 kJ × 1 mol) ÷ 5471 kJ
X = 0.970 moles of Ocatne
So, 0.970 moles of Octane will liberate 5310 kJ energy. Now changing moles to mass,
As,
Moles = mass / M.mass
Or,
Mass = Moles × M.mass
Putting values,
Mass = 0.970 mol × 114.23 g/mol
Mass = 110.83 g of Octane
Answer: 1.67 kg
Explanation:
The quantity of heat required to raise the temperature of a substance by one degree Celsius is called the specific heat capacity.

Q = Heat absorbed=
=
(1kJ=1000J)
m= mass of substance = ?
c = specific heat capacity = 
Change in temperature ,
Putting in the values, we get:

(1kg=1000g)
Thus the mass (in kg) of the copper sample is 1.67
Explanation:
how are you confused there just tell me the problem
Answer: It is called a Crookes Tube, and he used it to discover cathode rays, which were later determined to be electrons.