<span> the first ionization </span>energy<span> of an element is the </span>energy<span> needed to</span>remove<span> the outermost, or highest </span>energy<span>, </span>electron<span> from a neutral </span>atom<span> in the gas phase.</span>
First step: convert 22.4% into fraction
that is 22.4/100 which is equivalent to 0.224
The mass of Cucl2 contained in 75.85 of 22.4% by mass of solution of CUcl2 in water is therefore,
0.224 x75.85=16.99g
alternatively
75.85 --->100%
? 22.4%
by cross multiplication =(22.4 x 75.85)/100 =16.99g
Nuclear reactions are those that involve the nucleus of an atom. Nuclear fission involves the splitting of an atomic nucleus and the formation of two distinct atomic species. Nuclear fusion is indeed the combining of two atomic nuclei in order to form a single atomic species. Therefore the answer to the question is true.
20 cups of flour, 30 eggs, and 10 cups of sugar
Explanation:
12)
a) Sodium + oxygen = ?
When sodium reacts oxygen its forms sodium oxide as a product.

b) magnesium + fluorine = ?
When magnesium reacts with fluorine its forms magnesium fluoride as a product.

13)
a) 
Decomposition of mercury(II) oxide on heating gives out mercury and oxygen gas.
b)
The electrolytic decomposition of water gives out hydrogen gas amd oxygen gas.