Must contain: 6 protons, 6 electrons and 12 neutrons.
1) Find the number of mols of HCl in 5.2 liters of 4.0M solution:
n = M*V(L) = 4.0 mol/L * 5.2 L = 20.8 mol
2) Find the number of mols of Mg that will react with 20.8 mol of HCl, using the coefficients of the balanced equation
[1mol Mg / 2 mol HCl] * 20.8 mol HCl = 10.4 mol Mg
3) Transform mol to mass using the atomic mass:
10.4 mol Mg * 24.3 g/mol = 252.7 g of Mg.
Answer:
22.9 Liters CO(g) needed
Explanation:
2CO(g) + O₂(g) => 2CO₂(g)
? Liters 32.65g
= 32.65g/32g/mol
= 1.02 moles O₂
Rxn ratio for CO to O₂ = 2 mole CO(g) to 1 mole O₂(g)
∴moles CO(g) needed = 2 x 1.02 moles CO(g) = 2.04 moles CO(g)
Conditions of standard equation* is STP (0°C & 1atm) => 1 mole any gas occupies 22.4 Liters.
∴Volume of CO(g) = 1.02mole x 22.4Liters/mole = 22.9 Liters CO(g) needed
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*Standard Equation => molecular rxn balanced to smallest whole number ratio coefficients is assumed to be at STP conditions (0°C & 1atm).
Answer:
oxygen and silicon, both are common
Answer:
(a) Alkali metals: Francium (Fr)
(b) Chalcogens: Polonium (Po)
(c) Noble gases: Radon (Rn)
(d) Alkaline earth metals: Radium (Ra)
Explanation:
In the periodic table, the atomic mass increases down the group. Therefore, the last element of a group is the heaviest element of the group.
(a) alkali metals: The chemical elements that are present in group 1 of the periodic table, except hydrogen.
<u>The heaviest member of this group is francium (Fr)</u>
(b) chalcogens: The chemical elements that are present in group 16 of the periodic table
<u>The heaviest member of this group is polonium (Po)</u>
(c) noble gases: The chemical elements that are present in group 18 of the periodic table
<u>The heaviest member of this group is radon (Rn)</u>
(d) alkaline earth metals: The chemical elements that are present in group 2 of the periodic table.
<u>The heaviest member of this group is radium (Ra)</u>
