All categories

3 years ago

Given 20.0 g of (NH4)3 PO3 how many moles is this? How many formula units is it? How many hydrogen atoms are present?

Chemistry

1 answer:

Setler79 [48]3 years ago

8 0

Answer:

no of moles = (mass) ÷ molar mass

you get the molar mass from the periodic table

n = 20.0g ÷ ( 149.09 g/mol )

= 0.134 mol

number of formula units = number of moles × (6.022×10^23)

= 8.07×10^22 units

number of hydrogen atoms in (NH4)3 PO3 = 12 × number of formula units

= 9.68×10^23 hydrogen atoms

You might be interested in

Why does earth have uranium

Rainbow [258]

The isotope U-235 is important because under certain conditions it can readily be split, yielding a lot of energy. It is therefore said to be 'fissile' and we use the expression 'nuclear fission'. Meanwhile, like all radioactive isotopes, they decay.

5 0

3 years ago

Read 2 more answers

8. The time period of artificial satellite in a circular orbit of radius R is T. The radius of the orbit in which time period is

Elena-2011 [213]

Explanation:

It is given that,

The time period of artificial satellite in a circular orbit of radius R is T. The relation between the time period and the radius is given by :

$T^2\propto R^3$

The radius of the orbit in which time period is 8T is R'. So, the relation is given by :

$(\dfrac{T}{T'})^2=(\dfrac{R}{R'})^3$

$(\dfrac{T}{8T})^2=(\dfrac{R}{R'})^3$

$\dfrac{1}{64}=(\dfrac{R}{R'})^3$

$R'=4\times R$

So, the radius of the orbit in which time period is 8T is 4R. Hence, this is the required solution.

4 0

3 years ago

The strength of a covalent bond depends upon the size of the atoms and the bond order. In general short bonds are strong bonds.1

Oksana_A [137]

Answer:

Bond energy of (A) C≡C > (B) C=C

and, (C) C=N > (D) C-N

Explanation:

Bond energy refers to the amount of energy required to break a bond or the energy released when a bond is formed. Bond energy of a covalent bond suggests the bond strength of the chemical bond and depends on the bond length and bond order of the chemical bond.

The bond energy of a chemical bond increases with the bond order and decreases with the bond length. As, length of a bond decreases with increase in the bond order.

First pair: (A) C≡C (B) C=C

The bond order of C≡C - 3, the bond order of C=C - 2

Since the bond order: C≡C > C=C

Bond length: C≡C < C=C

Therefore, bond energy of (A) C≡C > (B) C=C

Second pair: (C) C=N (D) C-N

The bond order of C=N - 2, the bond order of C-N - 1

Since the bond order: C=N > C-N

Bond length: C=N < C-N

Therefore, bond energy of (C) C=N > (D) C-N

8 0

3 years ago

Give the name for the strongest intermolecular interaction between the substrate and the following amino acids on the star prote

mel-nik [20]

Answer:

The answer is IONIC BOND

Explanation:

Steroidogenic acute regulatory, (StAR) protein is a type of globular protein, which allows it act as an active catalyst on substrates. Because the substrates on which enzymes act usually have higher molecular weights of several hundred as compared to the enzymes, only a fraction of the enzyme's surface is in contact with the substrate. This region of contact called the active site, is as a result of the protein folding itself into a tertiary structure.

Once the correct substrate has bound at the active site of the enzyme, an enzyme-substrate complex is created. The substrate is usually held in the complex by combinations of electrical attraction, hydrophobic repulsion, or hydrogen bonding between and from the amino acid; the strongest of which is the ionic/electrostatic bonding due to larger amount of ionic "R" groups in the protein structure.

So whilst all these inter-molecular interactions are possible, the strongest would be ionic bond.

4 0

3 years ago

The combustion of 135 mg of a hydrocarbon produces 440 mg of CO2 and 135 mg H2O. The molar mass of the hydrocarbon is 270 g/mol.

NeX [460]

Answer:

Molecular formula = C20H30

Explanation:

NB 440mg = 0.44g, 135mg= 0.135g

From the question, moles of CO2= 0.44/44= 0.01mol

Since 1 mol of CO2 contains 1mol of C, it implies mol of C = 0.01

Also from the question, moles of H2O = 0.135/18= 0.0075mole

Since 1 mol of H2O contains 2mol of H, it implies mol of H = 0.0075×2= 0.015 mol of H

To get the empirical formula, divide by smallest number of mole

Mol of C = 0.01/0.01=1

Mol of H = 0.015/0.01= 1.5

Multiply both by 2 to obtain a whole number

Mol of C =1×2 = 2

Mol of H= 1.5×2 = 3

Empirical formula= C2H3

[C2H3] not = 270

[ (2×12) + 3]n = 270

27n = 270

n=10

Molecular formula= [C2H3]10= C20H30

5 0

3 years ago