Answer:
1. Fe + H2SO4 = FeSO4 + H2
iron + sulfuric acid = duretter + hydrogen
2. Mg + 2 HNO3 = Mg(NO3)2 + H2
Magnesium + nitric acid = magnesium nitrate +hydrogen
3. Zn + 2 HCl = ZnCl2 + H2
Zinc + hydrogen chloride= zinc chloride+ hydrogen
Option C: elements produce spectra with only few distinct lines.
The spectra are not continuos and are different for every element. This permits to identify elements.
H2S donates a proton, therefore it is a Brønsted-Lowry base; CH3NH2 accepts a proton, so it’s a Brønsted-Lowry base.
Answer:
The answer to your question is Molarity = 0.0708
Explanation:
Data
NaOH 0.05 M Volume 1 = 3.87 ml Volume 2 = 25.11 ml
HCl 15 ml
Process
1.- Find the volume used of NaOH
25.11 - 3.87 = 21.24 ml = 0.02124 l
2.- Write the balanced equation of the reaction
NaOH + HCl ⇒ NaCl + H₂O
3.- Calculate the moles of NaOH in the solution
Molarity = 
moles = Molarity x volume
moles = 0.05 x 0.02124
moles = 0.001062
4.- From the reaction we know that NaOH and HCl react in a proportion 1:1.
1 mol of NaOH ------------- 1 mol of HCl
0.001062 moles of NaOH ------------ x
x = (0.001062 x 1) / 1
x = 0.001062 moles of HCl
5.- Find the molarity of HCl
Molarity = 
Molarity = 0.0708