3. What bond angle is most closely associated with a trigonal planar distribution of electron density?...

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Answer 1

Answer #1

3) Which bond angle is most closely associated with a trigonal planar distribution of electron density ?

ANSWER : C . 120 ⁰

4) What is the formula weight of Ba₃(PO₄) ₂ ?

ANSWER : d. 601.9 amu

formula weight of Ba₃(PO₄) ₂ = ( 3 $\times$ 137.34 ) + ( 2 $\times$ 30.97) + ( 8 $\times$ 16.00) = 601.96 amu

5) Which of the following compound have largest formula weight ?

ANSWER : a. Aluminium acetate

Al(CH₃COO) ₃ = 26.98 + ( 6 $\times$ 12.01 ) + ( 9 $\times$ 1.0079 ) + ( 6 $\times$ 16.00 ) = 204.11 amu

CH₃COOK = ( 2 $\times$ 12.01 ) + ( 3 $\times$ 1.0079 ) + ( 2 $\times$ 16.00 ) + 39.10 = 98.14 amu

CH₃COONa= ( 2 $\times$ 12.01 ) + ( 3 $\times$ 1.0079 ) + ( 2 $\times$ 16.00 ) + 22.99 =82.03 amu

Ca(CH₃COO) ₂ = (4 $\times$ 12.01 ) + ( 6 $\times$ 1.0079 ) + ( 4 $\times$ 16.00 ) + 40.08 = 158.17 amu

6) A person drinks 1500 g of water per day . how many moles is this ?

ANSWER : c. 83.3

Molar mass of water is 18.01 g /mol.

We know that, no. of moles = Mass / molar mass

Hence, No. of moles of water = 1500 g / ( 18.01 g/mol) = 83.3 mol

7) How many Hydrogen atoms are there in 2.50 moles of C₆H₁₂O₆ ?

ANSWER : d 1.81 $\times$ 10 ²⁵

1 molecule of C₆H₁₂O₆ contain 12 Hydrogen atoms.

Hence, 1 mole C₆H₁₂O₆ contain 12 $\times$ N _A atoms.

$\therefore$ 2.50 mole C₆H₁₂O₆ contain 2.50 $\times$ 12 $\times$ N _A atoms. = 2.50 $\times$ 12 $\times$ 6.022 $\times$ 10 ²³ = 1.81 $\times$ 10 ²⁵

Answer 2