The thermochemical equation shows the combustion of carbon in oxygen. How many moles of carbon, C must be burnt to produce 196.5 kJ of heat?

Given thermochemical equation; C(s) + O2(g) -> CO2(g) = -393 kJ mol ‐¹

0.5 moles OF CARBON WILL BE BURNT SHOULD 196.5 kJ OF HEAT IS LIBERATED IN THE REACTION.

Explanation:

The standard heat of combustion of a substance is the heat evolved when one mole of the substance is burned completely in oxygen under standard conditions.

From the reaction, -393kJ of heat is required to burn 1 mole of Carbon completely in oxygen.

C(s) + O2 (g) > CO2(g)        -393 kJ mol^-1

Should 196.5 kJ of heat was evolved by the reaction, the number of moles of carbon to be produced will be x moles;

-393 kJmol^-1 of heat was required to burn 1 mole of Carbon

196.5 kJ/mol of heat will burn x moles of carbon.

x = ( 196.5 * 1 / -393)

x = -0.5 moles

0.5 moles of carbon will be burnt when 196.5 kJ of heat is liberated

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.

let that person have a turn to speak : )