Which metal in Period 5 is very reactive and has two valence electrons in each atom?
2 answers:
<u>Answer:</u> The correct answer is Strontium.
<u>Explanation:</u>
Reactivity of an element is defined as the tendency to loose or gain electrons. Reactivity decreases as we move from left to right in a period and it increases as we move from up to down in a group.
A metal which belongs to Period 5 and has 2 valance electrons is Strontium. This element belongs to Group 2.
The electronic configuration of strontium (Sr) =
Hence, the correct answer is Strontium.
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Answer:
57.1 kilo Joules of heat would be released.
Explanation:
ΔH°=-57.1kJ/mol
Molarity of HCl = 2.00 M
Molarity of NaOH = 1.00 M
According to reaction , 1 M of HCl reacts with 1 M of NaOH. Then 2.00 M of HCl will react with:
of NaOH
But according to question we only have 1.00 M NaOH .So, this means that NaOH is limiting reagent and HCl is an excessive reagent.
Heat evolved will depend upon concentration of NaOH solution :
Heat evolved when 1.00 M of NaOH reacts =
Negative sign means that heat is released during the reaction.
57.1 kilo Joules of heat would be released.