<span>Gloria is writing the
chemical formula for a compound using its chemical name. She has just
identified the names of the elements in the compound. The tool that she will
need to use next is a textbook to learn the IUPAC naming of compounds or a
handbook of chemical compounds.</span>
I think the answer is -12.7
Answer:
Pumice is a light colored, porous igneous rock. It forms during volcanic eruption occurring under water. It is an aggregate of concrete. Because of their porous nature they float over the surface of water. With time the pumice rocks undergoes with several changes including weathering, erosion, and transportation. The extent of heat and pressure, making the sediments of the pumice rocks into metamorphic rocks distinct in the chemical and physical composition of the parent material.
If concentration of HCl is 1 mol/dm³ :
m(<span>erlenmeyer flask) = 88,00 g.
m(Zn) = 25,0 g.
V(HCl) = 15 ml = 15 cm</span>³ = 0,015 dm³.
Chemical reaction: Zn + 2HCl → ZnCl₂ + H₂.
n(HCl) = c(HCl) · V(HCl).
n(HCl) = 1 mol/dm³ · 0,015 dm³ = 0,015 dm³.
n(Zn) = 25 g ÷ 65,4 g/mol = 0,38 mol.
n(H₂) = 0,015 mol ÷ 2 = 0,0075 mol.
m(H₂) = 0,0075 mol · 2g/mol = 0,015 g.