The true answer is: It's conserved because the total number of H atoms on each side is 12.
the first two answer is wrong because it's conserved not as mentioned, It's not conserved.
and the last one also wrong because the total number of O atoms are equal at the two sides but not equal 2.
Explanation:
The similarities between chemical and physical changes include change in state of matter and both process involve change in energy.
Chemical changes of a substance results in the formation of entirely new substances. These changes are not reversible.
Physical changes results in the change of the state of the substance which can be reversed.
However, both chemical and physical changes results in change of state of matter and both process results in change in energy.
Thus, we can conclude that the similarities between chemical and physical changes include change in state of matter and both process involve change in energy.
(it's alre answered but here it again 'NOTE: not my answer')
In this question we have given the gram of water and we know that 1 mole of water = 18 gram of water and 27 g of water contain 1.5 g of water 27 / 18 = 1.5 g
As we know that avogandro'S no is equal 6.022*1023
1.5g * 6.022*1023 = 9.0 * 1023 molecules present in each 27 g of water.
I hope you will understand better now if you like then comment below and tell me. Best of luck.