Answer:
See below
Explanation:
Each metal oxide reacts with HCl to form water and the metal chloride

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Answer:
70.77 g/mol is the molar mass of the unknown gas.
Explanation:
Effusion is defined as rate of change of volume with respect to time.
Rate of Effusion=
Effusion rate of oxygen gas after time t = 
Molar mass of oxygen gas = M = 32 g/mol
Effusion rate of unknown gas after time t = 
Molar mass of unknown gas = M'
The rate of diffusion of gas, we use Graham's Law.
This law states that the rate of effusion or diffusion of gas is inversely proportional to the square root of the molar mass of the gas. The equation given by this law follows:



M' = 70.77 g/mol
70.77 g/mol is the molar mass of the unknown gas.
Answer:
Explanation:
The chemical equation is:
There are several definitions of acid and bases: Arrhenius', Bronsted-Lowry's and Lewis'.
Bronsted-Lowry model defines and <em>acid</em> as a donor of protons, H⁺.
In the given equation HNO₃ is such substance: it releases an donates its hdyrogen to form the H₃O⁺ ion.
On the other hand, a <em>base</em> is a substance that accepts protons.
In the reaction shown, H₂O accepts the proton from HNO₃ to form H₃O⁺.
Thus, H₂O is a base.
In turn, on the reactant sides the substances can be classified as acids or bases.
H₃O⁺ contain an hydrogen that can be donated and form H₂O; thus, it is an acid (the conjugated acid), and NO₃⁻ can accept a proton to form HNO₃; thus it is a base (the conjugated base).