Answer:
<em>The correct option is A) Arrhenius</em>
Explanation:
According to the Arrhenius concept of acids and bases, an acid must produce H+ ions when it is present in a solution and the base must produce OH- ions when placed in a solution.
Ammonia does not contain OH- ions of its own when dissolved in water.
The reaction of ammonia dissolving is water can be written as:
NH3 + H2O ⇌ NH4+ + OH−
As we can see from the equation, ammonia does form OH- ions but it does not have OH- ions on its own.
Hence, according to the Arrhenius concept, NH3 is not a base.
Answer:
20.0928.
Explanation:
The average atomic mass is (90 * 19.992 + 10* 21) / 100
= 20.0928.
Beryllium, Magnesium, Calcium....etc have two valence electrons
"The solubility of gases decreases as temperature rises" statements about trends in solubility is accurate.
<u>Option: D</u>
<u>Explanation:</u>
A substance's solubility is the quantity of that component that is needed at a defined degree of temperature to produce a saturated solution in any set quantity of solvent. Some compounds like hydrochloric acid, ammonia, etc have solubility that reduces with rising temperature. They are both standard-pressure gases.
When heating a solvent with a gas absorbed in it, both the solvent and the solute spike in the kinetic energy.When the gaseous solute's kinetic energy rises, the molecules have a higher propensity to overcome the solvent molecules' connection and migrate to the gas phase. Thus, a gas's solubility reduces with rising temperature.
<em>V = 151 mL = 151 cm³</em>
<em>d = 0,789 g/mL = 0,789 g/cm³</em>
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d = m/V
m = d×V
m = 0,789×151
<u>m = 119,139g</u>