All categories

2 years ago

What is the oxidation number of pt in k2ptcl6?

1 answer:

4 0

Your compound is $K_{2}PtCl_{6}$ .

Remember that the oxidation numbers in a neutral compound must add up to zero. Cl has an oxidation number of -1 because it is a halogen K has an oxidation number of +1 because it is an alkali metal, which exhibits an oxidation state of +1 in compounds.

Since you have 6 atoms of Cl, you have -1(6) = -6 for the Cl. Since you 2 atoms of K, you have +1(2) = +2 for the K. The oxidation number of Pt must make all the oxidation numbers add up to zero:
+2 + (-6) + oxidation number of Pt = 0
-4 + oxidation number of Pt = 0
Oxidation number of Pt = 4

You might be interested in

Question 2: Phase Changes (14 points) a. Rewrite each of the following equations for phase changes, to include the heat required

lilavasa [31]

Explanation:

(i) The equilibrium reaction equation will be as follows.

$H_{2}O(l) \rightleftharpoons H_{2}O(s)$

A reaction in which there will be absorption of heat energy is known as endothermic reaction.

A reaction in which there will be release of heat energy is known as exothermic reaction.

As liquid state of water is changing into solid state. So, it means that molecules of water came close to each other. Hence, there will be release of heat this means that reaction is exothermic in nature.

Hence, phase change from liquid to solid will be exothermic in nature.

Latent heat of fusion is defined as the amount of energy necessary to convert 1 gram of a solid into liquid state at its melting point.

So, when solid state of water changes into liquid state then it means energy is absorbed by the molecules of ice due to which they have gained kinetic energy. Hence, they moved away from each other leading to formation of liquid state of water.

Latent heat of freezing of liquid water is 334 J/g.

Specific heat of liquid water is 4.186 $J/g ^{o}C$

Specific heat of steam is 1.996 $kJ/kg/^{o}K$

Specific heat of ice is 2.1 $kJ/kg/^{o}K$

(ii) The equilibrium reaction equation will be as follows.

$H_{2}O(l) \rightleftharpoons H_{2}O(g)$

As liquid state of water is changing into gaseous or vapor state. So, it means molecules of liquid water has gained kinetic energy hence, they colloid more rapidly with each other.

As a result, heat will be absorbed by the liquid state of water. Hence, heat will be absorbed. Therefore, phase change from liquid to gas will be endothermic in nature.

Whereas when gaseous state of water will change into liquid state then heat will be released during this process of condensation. As a result, in that case reaction will be exothermic in nature.

5 0

2 years ago

During an endothermic phase change, what happens to potential energy and the kinetic energy

polet [3.4K]

During this phase Change heat energy is being absorbed by the molecules, and as a result the molecules possess a greater ability to move around and possess higher kinetic energy because of this. The molecules also possess a higher potential energy.

7 0

2 years ago

Read 2 more answers

In a hydrogen fuel cell, hydrogen gas and oxygen gas are combined to form water. Write the balanced chemical equation describing

xxTIMURxx [149]

Answer: The chemical reaction is given below.

Explanation:

A fuel cell is defined as the electrochemical cell which converts the chemical energy of a fuel (often used hydrogen) and an oxidizing agent (often used oxygen) into electrical energy via a pair of redox reactions.

The reactions which occur in hydrogen-oxygen fuel cell are:

At cathode: $H_2+2OH^-\rightarrow 2H_2O+2e^-$

At anode: $\frac{1}{2}O_2+H_2O+2e^-\rightarrow 2OH^-$

Net reaction: $H_2+\frac{1}{2}O_2\rightarrow H_2O$

Thus, the chemical reaction is given above.

5 0

2 years ago

Read 2 more answers

Express each aqueous concentration in the unit indicated.

MAXImum [283]

Answer:

a. ppb of trichloroethylene = 3 × 10⁶ ppb

b. ppm of Cl₂ = 3.8 ppm

c. Molarity = 0.0002 mol / L

d. Molarity = 0.0007 mol / L

e. For trace amount of concentrations

Explanation:

a. Given data

mass of trichloroethylene = 25 mg

Volume of water = 9.5 L

ppb of trichloroethylene = ?

Solution

As we know that

1 L = 1000 milliliters

9.5 L = 9.5 × 1000

9.5 L = 9500 millileters (ml)

we consider 25 mg = 25 millileters

ppb = (mass of solute / mass of solvent) × 1000,000,000 (1 billion)

ppb of trichloroethylene = (25 ÷ 9500) × 1000,000,000

ppb of trichloroethylene = 0.003 × 1000,000,000

ppb of trichloroethylene = 3 × 10⁶ ppb

B. Given data

Mass of Cl₂ = 38 g

volume of water = 1.00 × 10⁴ L ( 10000 L)

ppm of Cl₂ = ?

Solution

Volume of water in ml = 1 L = 1000 ml

Volume of water in ml = 10000 × 1000

Volume of water in ml = 10000000 ml

we take 38 g = 38 ml

Now we convert it to ppm

ppm = (mass of solute / mass of solvent) × 1000000 (1 million)

ppm of Cl₂ = ( 38 ÷ 10000000 ) × 1000000

ppm of Cl₂ = 0.0000038 × 1000000

ppm of Cl₂ = 3.8 ppm

C. Given data

Concentration of F⁻ ( Fluoride ion) = 2.4 ppm

Molarity = ?

Solution

As we know that 1 ppm = 0.001 g / L

2.4 ppm = 2.4 × 0.001 g/L

2.4 ppm = 0.0024 g/L

Mass of flouride ions = 0.0024 g

Now we find number of moles

moles = mass / molar mass

molar mass of F⁻ = 19 g/mol

moles of F⁻ = 0.0024 g / 19 g/mol

moles of F⁻ = 0.0002 mol

Molarity = mol of solute / liter of solution

Molarity = 0.0002 mol / 1 L

Molarity = 0.0002 mol / L

D. Given data

Concentration of NO₃⁻ ( nitrate ion) = 45 ppm

Molarity = ?

Solution

As we know that 1 ppm = 0.001 g / L

45 ppm = 45 × 0.001 g/L

45 ppm = 0.045 g/L

Mass of nitrate ions = 0.045 g

Now we find number of moles

moles = mass / molar mass

molar mass of NO₃⁻ = 62 g/mol

moles of NO₃⁻ = 0.045 g / 62 g/mol

moles of F⁻ = 0.0007 mol

Molarity = mol of solute / liter of solution

Molarity = 0.0007 mol / 1 L

Molarity = 0.0007 mol / L

E. Reason of expressing concentration in ppm and ppb

Scientist prefer ppm and ppb notations when the concentration difference of solute and solvent are very high.

As water contains contaminants is a very low amount we can say in trace amounts so scientist prefer ppm and ppb rather than molarity.

Example

Arcenic is an under ground water contaminant and its concentration of 10 μg/L is dangerous for health.

Lets change this in to molarity

mass = 10 μg

10 μg = 10 / 1000000

10 μg = 0.00001 g

now find out moles of Arcenic

moles = mass / molar mass

molar mass of arcenic = 75 g/mol

moles = mass / molar mass

moles of arcenic = 0.00001 g / 75 g/mol

moles of arcenic = 0.00000012 mol

Molarity = moles of solute / litres of solution

Molarity = 0.00000012 mol / 1 L

Molarity = 0.00000012 mol/ L

As we can see that in molarity it is a negligible amount so scientists express it in ppm and ppb

7 0

2 years ago

Contractile proteins are found in _____.

Snowcat [4.5K]

Answer: In The Muscles

7 0

2 years ago

Read 2 more answers