Answer:
Explanation:
di) number of protons is 12 for all, number of neutrons is 13 for mg- 25 and 14 for mg-26
Answer: 19.4 mL Ba(OH)2
Explanation:
H2(g) + Cl2(g) --> 2HCl(aq) (make sure this equation is balanced first)
At STP, 1 mol gas = 22.4 L gas. Use this conversion factor to convert the 100. mL of Cl2 to moles.
0.100 L Cl2 • (1 mol / 22.4 L) = 0.00446 mol Cl2
Use the mole ratio of 2 mol HCl for every 1 mol Cl2 to find moles of HCl produced.
0.00446 mol Cl2 • (2 mol HCl / 1 mol Cl2) = 0.00892 mol HCl
HCl is a strong acid and Ba(OH)2 is a strong base so both will completely ionize to release H+ and OH- respectively. You need 0.00892 mol OH- to neutralize all of the HCl. Note that one mole of Ba(OH)2 contains 2 moles of OH-.
0.00892 mol OH- • (1 mol Ba(OH)2 / 2 mol OH-) • (1 L Ba(OH)2 / 0.230 M Ba(OH)2) = 0.0194 L = 19.4 mL Ba(OH)2
<span>Avogadro's number
represents the number of units in one mole of any substance. This has the value
of 6.022 x 10^23 units / mole. This number can be used to convert the number of
atoms or molecules into number of moles. We calculate as follows:
</span>1.40x10^23 molecules of N2 ( 1 mol / 6.022 x 10^23 molecules ) ( 28.02 g / mol ) = 6.51 g N2
Answer:
0.192 mol.
Explanation:
- To calculate the no. of moles of a substance (n), we use the relation:
<em>n = mass / molar mass.</em>
mass of AsH₃ = 15.0 g.
molar mass of AsH₃ = 77.95 g/mol.
∴ The number of moles in 15.0 g AsH₃ = mass / molar mass = (15.0 g) / (77.95 g/mol) = 0.192 mol.
Answer :
Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule. The electrons are represented by dot.
The given molecule is, perbromate ion.
Bromine has '7' valence electrons and oxygen has '6' valence electron.
Therefore, the total number of valence electrons in perbromate ion, 
= 7 + 4(6) + 1 = 32
According to Lewis-dot structure, there are 14 number of bonding electrons and 18 number of non-bonding electrons.
Formula for formal charge :
The Lewis-dot structure of perbromate ion is shown below.
