The answer is a i believe
<span>The SI base unit for distance is the meter</span>
Mass of Hydrogen gas required to react : 0.936 g
<h3>Further explanation</h3>
Reaction on Nitrogen gas and Hydrogen gas to produce Ammonia gas
N₂ (g) + 3 H₂ (g) ⇒ 2 NH₃ (g)
Conditions at T 0 ° C and P 1 atm are stated by STP (Standard Temperature and Pressure). At STP, Vm is 22.4 liters / mol
so mol Nitrogen for 3.5 L at STP :

From the equation, mol ratio of N₂ : H₂ = 1 : 3, so mol H₂ :

then mass of Hydrogen(MW= 2 g/mol) :

Answer:
E - Be and O
A - Mg and N
E - Li and Br
F - Ba and Cl
B - Rb and O
Explanation:
Be and O
Be is a metal that loses 2 e⁻ to form Be²⁺ and O is a nonmetal that gains 2 e⁻ to form O²⁻. For the ionic compound to be neutral, it must have the form BeO (E-MX).
Mg and N
Mg is a metal that loses 2 e⁻ to form Mg²⁺ and N is a nonmetal that gains 3 e⁻ to form O³⁻. For the ionic compound to be neutral, it must have the form Mg₃N₂ (A-M₃X₂).
Li and Br
Li is a metal that loses 1 e⁻ to form Li⁺ and Br is a nonmetal that gains 1 e⁻ to form Br⁻. For the ionic compound to be neutral, it must have the form LiBr (E-MX).
Ba and Cl
Ba is a metal that loses 2 e⁻ to form Ba²⁺ and Cl is a nonmetal that gains 1 e⁻ to form Cl⁻. For the ionic compound to be neutral, it must have the form BaCl₂ (F-MX₂).
Rb and O
Rb is a metal that loses 1 e⁻ to form Rb⁺ and O is a nonmetal that gains 2 e⁻ to form O²⁻. For the ionic compound to be neutral, it must have the form Rb₂O (B-M₂X).
<span>A cloud collapses to form a star and disk. Planets form from this disk.
According to our current understanding, a star and its planets form out of
a collapsing cloud of dust and gas within a larger cloud called a nebula
.his dense, hot core becomes the kernel of a new star.
Hoped this helped :D
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