Explanation:
When we move across a period from left to right then there will occur an increase in electronegativity and also there will occur an increase in non-metallic character of the elements.
As calcium (Ca) is a group 2A element and rubidium (Rb) is a group 1A element. Hence, Rb being an alkali metal is more metallic in nature than calcium (alkaline earth metal).
Both magnesium (Mg) and radium (Ra) are group 2A elements. And, when we move down a group then as the size of element increases so, it becomes easy of the metal atom to lose an electron.
As a result, there occurs an increase in metallic character of the element. Hence, Radium (Ra) is more metallic in nature than magnesium (Mg).
Also, both bromine and iodine are group 17 elements. Since, both of them are non-metals and non-metallic character increases on moving down the group.
Therefore, bromine (Br) is more metallic than iodine.
A.) half - life of a radioactive substance is defined as the time during which concentration of the substance becomes half the initial value.
Explanation:
The reaction is CaCO
3
+2HCl→CaCl
2
+H
2
O+CO
2
.
Thus, 2 moles of HCl reacts with one mole of calcium carbonate to produce one mole each of calcium chloride, water and carbon dioxide respectively.
Hence, 3 moles of HCl will react with excess of calcium carbonate to produce 3×
2
1
=1.5 mol of carbon dioxide
The new volume of the gas that has an initial pressure of 5.6 x 10⁵ Pa is 5.7L. Details about volume of the gas can be found below.
<h3>How to calculate volume?</h3>
The volume of a gas can be calculated using the Boyle's law equation as follows:
P1V1 = P2V2
Where;
- P1 = initial pressure
- P2 = final pressure
- V1 = initial volume
- V2 = final volume
1.53 × 5.6 × 10⁵ = 1.5 × 10⁵ × V2
8.568 × 10⁵ = 1.5 × 10⁵V2
V2 = 8.57 × 10⁵ ÷ 1.5 × 10⁵
V2 = 5.7L
Therefore, the new volume of the gas that has an initial pressure of 5.6 x 10⁵ Pa is 5.7L.
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