Answer: Option (C) is the correct answer.
Explanation:
In a substance, the total energy of its molecular motion is known as heat. Whereas when we measure the average energy of molecular motion of a substance then it is known as temperature.
So, any increase or decrease in temperature will lead to change in heat of a substance.
When one mole of a substance is burned then the amount of energy released in the form of heat is known as heat of combustion.
Relation between heat and temperature is as follows.
q = 
Thus, we can conclude that to measure the enthalpy of combustion it cannot be measured, only calculated using the equation; q =
.
Answer:
See Explanation
Explanation:
The question is incomplete; as the mixtures are not given.
However, I'll give a general explanation on how to go about it and I'll also give an example.
The percentage of a component in a mixture is calculated as:

Where
E = Amount of element/component
T = Amount of all elements/components
Take for instance:
In 
The amount of all elements is: (i.e formula mass of
)



The amount of calcium is: (i.e formula mass of calcium)



So, the percentage component of calcium is:




The amount of hydrogen is:



So, the percentage component of hydrogen is:




Similarly, for oxygen:
The amount of oxygen is:



So, the percentage component of oxygen is:




Answer: The density of the object will be 
Explanation:
Density is defined as the mass contained per unit volume.

Given : Mass of object = 19.6 grams
Volume of object= 
Putting in the values we get:

Thus density of the object will be 