Answer:
The net change in enthalpy for the formation of one mole of acrylic acid from calcium carbide, water and carbon dioxide is 523.2 kJ.
Explanation:
Step 1:
...[1]
Step 2 :
..[2]
Adding 6 × [1] and [2]:


we get :




Energy released on formation of 5 moles of acrylic acid = 2,626 kJ
Energy released on formation of 1 mole of acrylic acid:

Answer: The standard enthalpy of formation of
is -252.1 kJ/mol.
Explanation:
The balanced chemical reaction is,
The expression for enthalpy change is,
Putting the values we get :
Thus standard enthalpy of formation of
is -252.1 kJ/mol.
Yes ...................................
Answer:
THE NEW PRESSURE OF THE HELIUM GAS AT 2.98 L VOLUME IS 124.8 kPa.
AT AN INCREASE ALTITUDE, THERE IS A LOWER PRESSURE ENVIRONMENT AND THE HELIUM GAS PRESSURE DECREASES AND HENCE AN INCREASE IN VOLUME.
Explanation:
The question above follows Boyle's law of the gas law as the temperature is kept constant.
Boyle's law states that the pressure of a fixed mass of gas is inversely proportional to the volume, provided the temperature remains constant.
Mathematically, P1 V1 = P2 V2
P1 = 150 kPa = 150 *10^3 Pa
V1 = 2.48 L
V2 = 2.98 L
P2 = ?
Rearranging the equation, we obtain;
P2 = P1 V1 / V2
P2 = 150 kPa * 2.48 / 2.98
P2 = 372 *10 ^3 / 2.98
P2 = 124.8 kPa.
The new pressure of the gas when at a height which increases the volume of the helium gas to 2.98 L is 124.8 kPa.
Pure substances contain a single type of chemical species, either element or compound. Elements cannot be further broken into simpler units by chemical methods. If we consider a sample of elements, it has a single type of atoms present in it. A compound has one or more atoms bound together chemically. Compounds can be broken down into simpler units by chemical means. When we consider a sample of a single compound say water, it has all the pure water molecules. Hence, elements and compounds are pure substances.