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calculate the molar mass of nickel (iii)oxide to the nearest tenth place. Give both the numerial value and the units

maksim [4K]

Nickel (Ni) has the charge as +3 while oxygen (O) has -2. Hence, the chemical formula for the nickel (iii) oxide is Ni₂O₃.

molar mass of Ni = 58.69 g/mol
molar mass of O = 15.99 g/mol

number of Ni atoms in Ni₂O₃ = 2
Molar mass of Ni in Ni₂O₃ = 2 x 58.69 g/mol = 117.38 g/mol

number of O atoms in Ni₂O₃ = 3
Molar mass of O in Ni₂O₃ = 3 x 15.99 g/mol = 47.97 g/mol

Hence, molar mass of compound = 117.38 g/mol + 47.97 g/mol
= 165.35 g/mol
= 165.4 g/mol

8 0

4 years ago

How many grams of sodium acetate ( molar mass = 83.06 g/mol ) must be added to 1.00 Liter of a 0.200 M acetic acid solution to m

Pie

Answer: The mass of sodium acetate that must be added is 30.23 grams

Explanation:

To calculate the number of moles for given molarity, we use the equation:

$\text{Molarity of the solution}=\frac{\text{Moles of solute}}{\text{Volume of solution (in L)}}$

Molarity of acetic acid solution = 0.200 M

Volume of solution = 1 L

Putting values in above equation, we get:

$0.200M=\frac{\text{Moles of acetic acid}}{1L}\\\\\text{Moles of acetic acid}=(0.200mol/L\times 1L)=0.200mol$

To calculate the pH of acidic buffer, we use the equation given by Henderson Hasselbalch:

$pH=pK_a+\log(\frac{[\text{salt}]}{[\text{acid}]})$

$pH=pK_a+\log(\frac{[CH_3COONa]}{[CH_3COOH]})$

We are given:

$pK_a$ = negative logarithm of acid dissociation constant of acetic acid = 4.74

$[CH_3COONa]=?mol$

$[CH_3COOH]=0.200mol$

pH = 5.00

Putting values in above equation, we get:

$5=4.74+\log(\frac{[CH_3COONa]}{0.200})$

$[CH_3COONa]=0.364mol$

To calculate the mass of sodium acetate for given number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Molar mass of sodium acetate = 83.06 g/mol

Moles of sodium acetate = 0.364 moles

Putting values in above equation, we get:

$0.364mol=\frac{\text{Mass of sodium acetate}}{83.06g/mol}\\\\\text{Mass of sodium acetate}=(0.364mol\times 83.06g/mol)=30.23g$

Hence, the mass of sodium acetate that must be added is 30.23 grams

7 0

3 years ago

How to find the charge of an element

katrin2010 [14]

Answer:

the atomic number is how you find the charge

7 0

4 years ago

The photodissociation of ozone by ultraviolet light in the upper atmosphere is a first-order reaction with a rate constant of 1.

atroni [7]

Answer:

[O₃]= 8.84x10⁻⁷M

Explanation:

The photodissociation of ozone by UV light is given by:

O₃ + hν → O₂ + O (1)

The first-order reaction of the equation (1) is:

$rate = k [O_{3}] = - k \frac{\Delta [O_{3}]}{\Delta t}$ (2)

where k: is the rate constant and Δ[O₃]/Δt: is the variation in the ozone concentration with time, and the negative sign is by the decrease in the reactant concentration

We can get the following expression of the first-order integrated law of the reaction (1), by resolving the equation (2):

$[O_{3}]_{t} = [O_{3}]_{0} \cdot e^{-kt}$ (3)

where [O₃](t): is the ozone concentration in the elapsed time and [O₃]₀: is the initial ozone concentration

We can calculate the initial ozone concentration using equation (3):

$[O_{3}]_{t} = 5.0 \cdot 10^{-3}M \cdot e^{-(1.0\cdot 10^{-5}s^{-1}) (\frac{10d \cdot 24h \cdot 3600 s}{1d \cdot 1h})} = 8.84 \cdot 10^{-7}M$

So, the ozone concentration after 10 days is 8.84x10⁻⁷M.

I hope it helps you!

3 0

4 years ago

Classify the following processes as exothermic or endothermic: (d) a person running;

Sonja [21]

The process releases energy and consequently we classify it as exothermic. (d) a person running releases warmness as muscle mass paintings. therefore, the procedure is exothermic.

d) Exothermic, heat is released as a person runs and muscle groups perform work.

A chemical response or bodily exchange is exothermic if warmth is released by using the system into the environment. Because the surroundings are gaining heat from the system, the temperature of the surroundings increases. The sign of q for an exothermic procedure is -ve due to the fact the device is dropping heat.

Some other examples of exothermic reactions:

1)Snow Formation in Clouds.

2)Burning of a Candle.

3)Rusting of Iron.

4)Formation of Ion Pairs.

5)response of strong Acid and Water. etc...

Learn more about exothermic reactions here: brainly.com/question/14018816

#SPJ4

6 0

2 years ago