If I understand this right, the two elements are Nickel and Copper, elements 28 and 28, respectively. A nickel is worth 5 cents, and a penny, originally comprised of copper, is worth one - the total being six cents.
Answer:
33.33% = 33%
Explanation:
MgCO3(s) + 2HCl (aq) --> MgCl2(aq) + H20(l) + CO2(g)
1 mole of MCO3 will produce → 1 mole of CO2
We need to get the number of mole of CO2:
and when we have 0.22 g of CO2, so number of mole = mass / molar mass
Moles = 0.22 g / 44 g/mol = 0.005 mole
Moles of Mg = moles of CO2 = 0.005 mole
Mass of Mg = moles * molar mass
= 0.005 * 84 /mol = 0.42 g
Percent of MgCO3 by mass of Mg = 0.42 g / 1.26 * 100
=33.33 %
six commonly recognised metalloids are boron, silicon, germanium, arsenic, antimony, and tellurium. Five elements are less frequently so classified: carbon, aluminium, selenium, polonium, and astatine.
Answer:
The number of moles of Sr in one mole of Sr(HCO₃)₂ = 1 mole
The number of moles of H in one mole of Sr(HCO₃)₂ = 2 moles
The number of moles of C in one mole of Sr(HCO₃)₂ = 2 moles
The number of moles of O in one mole of Sr(HCO₃)₂ = 6 moles
Explanation:
The given chemical formula of the compound is Sr(HCO₃)₂
The number of atoms of Sr in the compound = 1
The number of atoms of H in the compound = 2
The number of atoms of C in the compound = 2
The number of atoms of O in the compound = 6
The number of atoms of each element present in each formula unit of Sr(HCO₃)₂ is proportional to the number of moles of each atom in one mole of Sr(HCO₃)₂
Therefore;
The number of moles of Sr in one mole of Sr(HCO₃)₂ = 1 mole
The number of moles of H in one mole of Sr(HCO₃)₂ = 2 moles
The number of moles of C in one mole of Sr(HCO₃)₂ = 2 moles
The number of moles of O in one mole of Sr(HCO₃)₂ = 6 moles.
