A. helium, neon and argon, because they are in the same group or column
Answer:
Explanation:
The mechanical properties of a material affect how it behaves as it is loaded. The elastic modulus of the material affects how much it deflects under a load, and the strength of the material determines the stresses that it can withstand before it fails
69.9%
Explanation:
To find the mass percentage of iron in the compound in Fe₂O₃, we would go ahead to express the given molar mass of the iron to that of the compound.
Mass percentage = 
x 100
Molar mass of Fe = 55.85g/mol
Molar mass of O = 16g/mol
Molar mass of Fe₂O₃ = 2(55.85) + 3(16) = 159.7g/mol
Mass percentage = 
= 69.94% = 69.9%
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In Na2O, what is the oxidation state of oxygen? In Na2O oxidation state of Na is 1+
Answer is: the ratio of the effusion rate is 1.59 : 1.
1) rate of effusion of carbon monoxide gas = 1/√M(CO).
rate of effusion of carbon monoxide gas = 1/√28.
rate of effusion of carbon monoxide gas = 0.189.
2) rate of effusion of chlorine = 1/√M(Cl₂).
rate of effusion of chlorine = 1/√70.9.
rate of effusion of chlorine = 0.119.
rate of effusion of carbon monoxide : rate of effusion of chlorine =
= 0.189 : 0.119 / ÷0.119.
rate of effusion of carbon monoxide : rate of effusion of chlorine = 1.59 : 1.
