Answer:
Ba,Sr,Ca,Be
Explanation:
as atomic size increases ionisation potential decreases
<span>-NH2 or, in its ionized form, -NH3+. Amino groups are the functional groups that bestow the "amino" in amino acid. They also readily ionize, gaining a proton (hydrogen ion), and thus serve as weak bases.</span>
A. They will Attract to each other
7.5 ppm
<h3>Further explanation</h3>
Given
1000 g of water
0.0075g of Ca²⁺ ion
Required
the concentration in ppm by mass of Ca²⁺
Solution
ppm = part per million
solvent = water ⇒ ppm = 1 mg/L(water density is 1 kg / L) or mg/kg
Convert g to mg of Ca²⁺ ion :
0.0075 g = 7.5 x 10⁻³ g = 7.5 mg
Convert g to kg of water :
1000 g = 1 kg water
So the concentration of Ca²⁺ ion :
= 7.5 mg / 1 kg
= 7.5 ppm