Answer:
1.42 moles
Explanation:
25.58 g of H₂O .
Molecular weight of water = 2 x 1 + 16 = 18
1 mole of water = 18 g of water
18 g of water = 1 mole
25.58 g of water = 25.58 / 18 mole
= 1.42 moles .
Fluorine ions reacts with Hydrogen chloride to form more hydrogen fluoride.
Therefore, moles of HCl = 0.005 l × 0.01 M = 5 ×10^-5 moles
The initial moles of Hydrogen fluoride will be;
= 0.0126 M× 0.0250 = 0.00315 Moles
Moles of hydrogen fluoride after the addition of HCl
= 0.00315 + 5.0× 10^-5 = 0.0032 moles
Therefore, the concentration of Hydrogen chloride
= 0.0032 moles/ 0.030 L
= 0.107 M
The change in state from Liquid ➡ gas describes the process of evaporation.
The mass of calcium hydroxide that is formed when 10.0 g of CaO reacts with 10.0 g of water is 13.024 grams
calculation
from the equation
CaO + H2O → Ca(OH)2,
1 moles of CaO reacted with 1 moles of H2O to form 1 moles of Ca(OH)2
find the moles of each reactant
moles=mass/molar mass
moles of CaO= 10 g/56 g/mol=0.179 moles
moles of H2O = 10 g/18 g/mol 0.556 moles
CaO is the limiting reagent therefore by use of mole ratio of CaO:Ca(OH)2 which is 1:1 moles of Ca(OH)2 is = 0.179 moles
mass= moles x molar mass
= 0.176 moles x 74 g/mol = 13.024 grams
The atomic number(Z) is equal to the number of protons to equal to number of electrons.
The number of neutrons is equal to atomic mass minus the atomic number
n=A-Z
For Zn^2+, Z=28, e=28
For iron, Z=25,A=55
The number of neutrons is 55-25=30
The charge is zero
For O^2-, Z=8+2=10, n=p=10
The number of neutrons is 16-10=6
For sulfur, Z=16,A=34
For S2-, Z=16+2=18, A=34
The charge is 2-
- The atomic number is the basis of the periodic table.
- It is equal to the number of protons.
- The number of neutrons is atomic mass minus atomic number.
To learn more about atomic number visit:
brainly.com/question/16858932
#SPJ1
