I think the correct answer from the list of choices above is option B. <span>The chemical combination of two or more different atoms in fixed amounts is called a compound. There are two type of compounds namely the ionic and covalent compounds.</span>
The relative molecular mass of the gas : 64 g/mol
<h3>Further explanation</h3>
Given
Helium rate = 4x an unknown gas
Required
The relative molecular mass of the gas
Solution
Graham's Law

r₁=4 x r₂
r₁ = Helium rate
r₂ = unknown gas rate
M₁= relative molecular mass of Helium = 4 g/mol
M₂ = relative molecular mass of the gas
Input the value :

Answer:
10.8 days (3 sig.figs.)
Explanation:
All radioactive decay is 1st order decay defined by the expression A = A₀e^-kt
which is solved for time of decay (t) => t = ln(A/A₀) / -k
A = final weight = 1.0 gram
A₀ = initial weight = 16.0 grams
k = rate constant = 0.693/t(1/2) = 0.693/2.69 days = 0.258 days⁻¹
t = ln(1/16) / -0.258da⁻¹ = (-2.77/-0.258) days = 10.74646792 days (calculator)
≅ 10 days (1 sig. fig. based on given 1 gram mass)
The chemical formula for chlorophyll is C55H72O5N4<span>Mg. Only 1 of the 137 atoms comes from magnesium.
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The pressure of the nitrogen gas produced is determined as 44.77 atm.
<h3>
What is the pressure of the Nitrogen gas?</h3>
The pressure of the nitrogen gas is determined from ideal gas equation, as shown below;
PV = nRT
P = nRT/V
where;
- n is number of moles = 2 moles
- R is ideal gas constant = 0.08205 L.atm/mol.K
- T is temperature = 68⁰C = 68 + 273 = 341 K
- V is volume = 1.25 L
P = (2 x 0.08205 x 341)/(1.25)
P = 44.77 atm.
Learn more about pressure here: brainly.com/question/25736513
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