<span>A.H2O = water, so it is a liquid at room temperatures (melting point = 0C) and melting point must be below 20C
B.HCl = A gas at room temperatures, so melting point (-114C) is definitely lower than 20C.
Melting points of the aqueous solution (solution in water) at different concentrations are all below that of water, i.e. 0C.
C.CH4 = A gas at room temperatures, so melting point (-182C) must be below 20C.
D.MgCl2 = A white powdery solid at room temperatures, so its melting point (714C) must be above 20C (So this is the only one among the four choices that melts above 20 ° C).</span>
Cells are surrounded by #2 , Cell membrane and Cell wall thats what protects the cell
The number of mole of lithium, Li needed for the reaction is 3.2 moles (Option D)
<h3>Balanced equation </h3>
4Li + N₂(g) → 2Li₂N
From the balanced equation above,
2 moles of Li₂N were obtained from 4 moles of Li
<h3>How to determine the mole of lithium needed </h3>
From the balanced equation above,
2 moles of Li₂N were obtained from 4 moles of Li
Therefore,
1.6 moles of Li₂N will be obtained from = (1.6 × 4) / 2 = 3.2 moles of Li
Thus, 3.2 moles of Li are needed for the reaction
Learn more about stoichiometry:
brainly.com/question/14735801
Answer:
I'm pretty sure it's neutrons the first one
