Answer:
3). Chemical potential energy
1). lower in charcoal than in coal.
Explanation:
Chemical potential energy is defined as the energy that can be absorbed or stored in a substance's chemical bonds. It can be released when there is a change in the number of particles of the substance.
As per the question, coal releases more heat than charcoal because 'the chemical potential energy of charcoal is lower than the coal' <u><em>and hence, the latter would release more heat on burning i.e. the energy that was absorbed in the chemical bonds of the substance</em></u>. Hence, option 3 and 1 are the correct answers.
Answer:
A. CaO
Explanation:
Reactant are the species that take part in and also undergoes the reaction to form species which are known as products.
Symbolic representation of the chemical reaction with the help of the formulas and symbols is known as chemical equation. In the chemical equation, reactants are written at left-hand side as well as products are expressed or written on right-hand side. The coefficients which are written before the formulas or the symbols are known as stoichiometric numbers.
Thus, in the reaction shown below:-

<u>Thus, The product of the reaction is:- CaO</u>
Answer:
A = 65.46 u
Explanation:
Given that,
The composition of zinc is as follows :
Zn-64 = 48.63%
Zn-66 = 27.90%
Zn-67 = 4.10%
Zn-68 = 18.75%
Zn-70 = .62%
We need to find the average atomic mass of the given element. It can be solved as follows :

So, the average atomic mass of zinc is 65.46 u.
<span>1 liter of drink contain water = 15%
12l of drink contain water = 15 %
12l of drink contain water at 15% = 1.8l
12l of drink contain water at 50% = 6l
Water to add in 15% water drink = 6l – 1.8l = 4.2l
After adding 4.2l of water in 12l 15% water drink, we get 50% water drink.</span>
Answer : 0.125 M
Explanation : The definition of osmotic pressure is "<span><em>the pressure can be applied on a pure solvent to prevent it passing into a given solution by osmosis</em>".
</span>
So according to this definition, osmotic pressure can be called as directly proportional to the concentration of the solution and hence the pressure can also be directly proportional to the concentration.
Hence, if pressure is getting decreased from 28 to 7 it means it got decreased by 4 times;
28 / 7 = 4 that means;
So the concentration will be also decreased by 4 times so, 0.50 / 4 = 0.125 M