Answer : The heat of the reaction is -221.6 kJ
Explanation :
Heat released by the reaction = Heat absorbed by the calorimeter


where,
= heat released by the reaction = ?
= heat absorbed by the calorimeter
= specific heat of calorimeter = 
= change in temperature = 
Now put all the given values in the above formula, we get:


As, 
So, 
Thus, the heat of the reaction is -221.6 kJ
<h3>During physical changes, the composition od the original substance is not altered, but the properties of the original substance are altered. During a chemical change the composition od the original substance is not altered and the change is irreversible. Melting of butter and wax is an example of chemical changes.</h3>
Answer:
An alloy is a metal made up of multiple metals giving it more strength.
Some examples may be a cast iron pot, rings, stainless steel sinks, instruments like the saxophone, door knobs, some keys, and some tools. Hope this helps some :)
Explanation:
Answer:
Mass of reactant and mass of product must be equal.
Explanation:
Law of conservation of mass:
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
Explanation:
This law was given by French chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
For example:
In given photosynthesis reaction:
6CO₂ + 6H₂O + energy → C₆H₁₂O₆ + 6O₂
there are six carbon atoms, eighteen oxygen atoms and twelve hydrogen atoms on the both side of equation so this reaction followed the law of conservation of mass.
Answer : The moles of given compound is, 0.064 mole
Explanation : Given,
Mass of given compound = 40 g
Atomic mass of X = 50 amu
Atomic mass of Y = 45 amu
Atomic mass of Z = 10 amu
First we have to calculate the molar mass of given compound.
The given compound formula is, 
Molar mass of
= (5 × Atomic mass of X) + (7 × Atomic mass of Y) + (6 × Atomic mass of Z)
Molar mass of
= (5 × 50) + (7 × 45) + (6 × 10) = 625 g/mol
Now we have to calculate the moles of given compound.



Thus, the moles of given compound is, 0.064 mole