Answer:
2.7724 g
Explanation:
Mass of pre- 1892 pennies = 3.1 g
Abundance = 45.4 %
Mass of post 1892 pennies = 2.5 g
Abundance = 100 - 45.4 = 54.6 %
The average mass is given as = ( 3.1 g * 45.4 / 100) + (2.5g * 54.6 / 100)
Average Mass = 3.1 * 0.454 + 2.5 * 0.546
Average Mass = 1.4074 + 1.365 = 2.7724 g
Answer: D. the hardening of liquid magma that leads to igneous rock
Explanation:
Fe2+:ferrous ion; fe3+ ferric ion are the one which are correctly named(Answer A) Sn2+ are called stannous ion while Sn4+ are known as stannic ions. Pb2+ are called lead (II) ions while Pb4+ are known as lead (IV) ion Co2+ are known was cobalt (II) ions while Co3+ are known as cobalt(IIi) ion.