Answer: 6.38 moles of
are needed to react with 2.55 mol of 
Explanation:
The balanced chemical reaction for the combustion of ethyne is:

According to stoichiometry:
2 moles of
require = 5 moles of 
Thus 2.55 mol of
require =
moles of 
Thus 6.38 moles of
are needed to react with 2.55 mol of 
Answer:cathode
Explanation:It is also known as the galvanic cell or electrochemical cell. In the voltaic cell, the oxidation occurs at an anode which is a negative electrode and the reduction occurs at the cathode which is a positive electrode.
Answer:
The mass of the surrounding is 
Explanation:
From the question we are told that
The mass of
is 
The mass of water is 
The chemical equation for the dissociation process is

The specific heat capacity of the mixture is 
The combined mass of the solution is

The mass of the surround here is the mass of the coffee-cup calorimeter and this contain the mixture ( water and the NaOH ) so the mass of the surrounding is

Answer:
it can last for 30 minutes
Explanation:
because it is very good at giving off heat, extothermal heat can last for quite a while.
Answer : The rate of effusion of sulfur dioxide gas is 52 mL/s.
Solution :
According to the Graham's law, the rate of effusion of gas is inversely proportional to the square root of the molar mass of gas.

or,
..........(1)
where,
= rate of effusion of nitrogen gas = 
= rate of effusion of sulfur dioxide gas = ?
= molar mass of nitrogen gas = 28 g/mole
= molar mass of sulfur dioxide gas = 64 g/mole
Now put all the given values in the above formula 1, we get:


Therefore, the rate of effusion of sulfur dioxide gas is 52 mL/s.