Atoms are made of subatomic particles is the statement among the statements given in the question that is not a part of John Dalton;s atomic theory. The correct option among all the options given in the question is the second option or option "B". I hope the answer helps you.
Answer : The mass of the water in two significant figures is, 
Explanation :
In this case the heat given by the hot body is equal to the heat taken by the cold body.
where,
= specific heat of iron metal = 
= specific heat of water = 
= mass of iron metal = 32.3 g
= mass of water = ?
= final temperature of mixture = 
= initial temperature of iron metal = 
= initial temperature of water = 
Now put all the given values in the above formula, we get
Therefore, the mass of the water in two significant figures is,
Answer:
it will halves
Explanation:
if the volume is doubled then the pressure is halves.
Simply saying, enthalpy is the measure of heat content of a system at constant pressure. Thus it is the thermodynamic potential of a system, which is obtained by summing internal energy(U) & Product of pressure(p) & volume(V) of a system.
<h3>
Answer:</h3>
12 years
<h3>
Explanation:</h3>
We are given;
Half life of hydrogen-3 is 12 years
Initial mass of Hydrogen-3 is 20 grams
Final mass will be 10 g because we are told half of the sample will decay.
To find the time taken for the decay we need to know what half life is;
- Half life is the time taken for a radioactive isotope to decay to half its original amount.
Remaining mass = Original mass × 0.5^n
n = number of half lives
therefore;
10 g = 20 g × 0.5^n
0.5 = 0.5^n
n = log 0.5 ÷ log 0.5
= 1
But, 1 half life is 12 years
Therefore, the time taken is 12 years
