Answer:
The answer to your question is :
a) Abundance of Li-6 = 7.49
b) Abundance of Li-7 = 100-7.49 = 92.5
Explanation:
Data Isotopes Mass Abundance
Li-6 6.015 amu y
Li-7 7.016 amu 100 -y
Lithium atomic mass = 6.941
6.941 = (6.015y) + (7.016)(100-y) /100
6.941 = (6.015y + 701.6 - 7.016y) / 100
6.941 x 100 = 6.015y - 7.016y + 701.6
694.1 -701.6 = - 1.001y
-7.5 = -1.001 y
y = 7.49
Abundance of Li-6 = 7.49
Abundance of Li-7 = 100-7.49 = 92.5
Answer:
Explanation:
Molecular mass of methanoic acid (HCOOH) = 2*1 + 1*12 + 2*16
=46 grams
mass of 1 mole of hydrogen atom = 1 g
mass of 1 mole carbon atom = 12 g
mass of 1 mole of oxygen atom = 16 g
mass of 1 mole of HCOOH = 46 g
1 mole of HCOOH molecule contains 1 mole of carbon atoms
means in 46 g of HCOOH there is 12 g of carbon atoms.
Percentage of carbon in methanoic acid =
Answer:
1) 1 N2 + 3 H2 2 NH3
2) 2 KClO3 2 KCl + 3 O2
3) 2 NaCl + 1 F2 2 NaF + 1 Cl2
4) 2 H2 + 1 O2 2 H2O
5) 1 Pb(OH)2 + 2 HCl 2 H2O + 1 PbCl2
6) 2 AlBr3 + 3 K2SO4 6 KBr + 1 Al2(SO4)3
7) 1 CH4 + 2 O2 1 CO2 + 2 H2O
8) 1 C3H8 + 5 O2 3 CO2 + 4 H2O
9) 2 C8H18 + 25 O2 16 CO2 + 18 H2O
10) 1 FeCl3 + 3 NaOH 1 Fe(OH)3 + 3 NaCl
11) 4 P + 5 O2 2 P2O5
12) 2 Na + 2 H2O 2 NaOH + 1 H2
13) 2 Ag2O 4 Ag + 1 O2
14) 1 S8 + 12 O2 8 SO3
15) 6 CO2 + 6 H2O 1 C6H12O6 + 6 O2
16) 1 K + 1 MgBr 1 KBr + 1 Mg
17) 2 HCl + 1 CaCO3 1 CaCl2 + 1 H2O + 1 CO2
18) 1 HNO3 + 1 NaHCO3 1 NaNO3 + 1 H2O + 1 CO2
19) 2 H2O + 1 O2 2 H2O2
20) 2 NaBr + 1 CaF2 2 NaF + 1 CaBr2
21) 1 H2SO4 + 2 NaNO2 2 HNO2 + 1 Na2SO4
(RECTANGLES ARE ARROWS)
A pair of oxygen atoms can form an O2 molecule in which each atom has a total of eight valence electrons by sharing two pairs of electrons. The term covalent bond is used to describe the bonds in compounds that result from the sharing of one or more pairs of electrons.