The pairs are:
K, Kr - Same period
Be, Mg - Same group
Ni, Tc - Both are transition metals
B, Ge - Both are metaloids
Al, Pb - Both form inert oxides
Answer: B. It’s a dilute strong base.
Explanation:
1) Definition of acids and bases: as per Bronsted-Lowry model, an acid is a substance that donates hydrogen ions and a base is a substance that accepts hydrogen ions.
Ca(OH)₂ does not have hydrogen ions to donate, but it can accept hydrogen ions to form H₂O according to this equation: H⁺ + OH⁻ → H₂O.
Hence, Ca(OH)₂ is a base.
2) Definition of strong base: a strong base is a base that dissociates completely into metallic and hydroxide ions in aqueous solutions, while a weak base dissociates partially.
Hence, Ca(OH)₂ is a strong base.
3) Definition of dilute: it refers to a solution meaning that the substance is not pure and the concentration is low. Since, the solution the Ca(OH)₂ is 0.02 M means that it is dilute.
Therefore, we have found that the description of 0.02 M Ca(OH)₂ is that is is a dilute strong base (option B).
Explanation:
Reaction equation for the given chemical reaction is as follows.
Equation for reaction quotient is as follows.
Q = 
= 
= 0.256
As, Q > K (= 0.12)
The effect on the partial pressure of 
as equilibrium is achieved by using Q, is as follows.
- This means that there are too much products.
- Equilibrium will shift to the left towards reactants.
- More is formed.
- Partial pressure of increases.
Answer:
The masses of the reactants and products are equal.
Explanation:
Hope this helps.
