Cp stands for specific heat.
Answer:
Group 2A — The Alkaline Earth Metals. Group 2A (or IIA) of the periodic table are the alkaline earth metals: beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra).
Explanation:
1) B+3 is ok. The exercise already put B+3. What
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2) Ge is a neutral atom because it doesn't have any charge.
Germanium has 32 electrons and 32 protons because its atomic number is 32.
Be careful with that.
Neutral atoms have the same numbers of electrons and protons.
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3)
Answer:
The both compounds are different.
Explanation:
In order to confirm weather both compounds are same we will check the mole ration. If it is same the compounds will be same.
Given data:
For compound 1.
Mass of hydrogen = 15 g
Mass of oxygen = 120 g
Moles of hydrogen and oxygen = ?
Number of moles of hydrogen = 15 g/ 1g/mol = 15 mol
Number of moles of oxygen = 120 g/ 16 g/mol = 7.5 mol
Total number of moles = 22.5 mol
% of hydrogen = 15 /22.5 × 100 = 66.7%
% of oxygen = 7.5 / 22.5× 100 = 33.3%
For compound 2:
Mass of hydrogen = 2 g
Mass of oxygen = 32 g
Moles of hydrogen and oxygen = ?
Number of moles of hydrogen = 2 g/ 1g/mol = 2 mol
Number of moles of oxygen = 32 g/ 16 g/mol = 2 mol
Total number of moles = 4 mol
% of hydrogen = 2 /4 × 100 = 50%
% of oxygen = 2 / 4× 100 = 50%
When we can get Pka for K2HPO4 =6.86 so we can determine the Ka :
when Pka = - ㏒ Ka
6.86 = -㏒ Ka
∴Ka = 1.38 x 10^-7
by using ICE table:
H2PO4- → H+ + HPO4
initial 0.4 m 0 0
change -X +X +X
Equ (0.4-X) X X
when Ka = [H+][HPO4] / [H2PO4-]
by substitution:
1.38 X 10^-7 = X^2 / (0.4-X) by solving for X
∴X = 2.3x 10^-4
∴[H+] = X = 2.3 x 10^-4
∴PH = -㏒[H+]
= -㏒ (2.3 x 10^-4)
∴PH = 3.6
