Consider these chemical equations. N2(g) + 3H2(g) → 2NH3(g)
C(s) + 2H2(g) → CH4(g)
4H2(g) + 2C(s) + N2(g) → 2HCN(g) + 3H2(g)

Which equation(s) do you need to reverse in order to calculate the overall equation for the formation of HCN and H2 from NH3 and CH4? Check all that apply.

An atom of lithium-7 has an equal number of(1) electrons and neutrons(2) electrons and protons(3) positrons and neutrons(4) positrons and protons

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)

Amines are good nucleophiles, even though they are neutral molecules. how would the rate of an sn2 reaction between an amine and an alkyl halide be affected if the polarity of the solvent is increased? amines are good nucleophiles, even though they are neutral molecules. how would the rate of an reaction between an amine and an alkyl halide be affected if the polarity of the solvent is increased? because both reactants in the rate-limiting step are neutral, the reaction will be faster if the polarity of the solvent is increased. because both reactants in the rate-limiting step are neutral, the reaction will be slower if the polarity of the solvent is increased. because both reactants in the rate-limiting step are neutral, the reaction will occur at the same rate if the polarity of the solvent is increased. request answer