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1 year ago

What is called a measurement and does involve a number and unit in chemistry?

Chemistry

1 answer:

marta [7]1 year ago

3 0

Answer:

1.1: Taking Measurements. Chemists measure the properties of matter and express these measurements as quantities. A quantity is an amount of something and consists of a number and a unit. The number tells us how many (or how much), and the unit tells us what the scale of measurement is.

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mixture of N 2 And H2 Gases weighs 13.22 g and occupies a volume of 24.62 L at 300 K and 1.00 atm.Calculate the mass percent of

anygoal [31]

Answer: The mass percent of nitrogen gas and hydrogen gas is 91.41 % and 8.59 % respectively.

Explanation:

To calculate the number of moles, we use the equation given by ideal gas equation:

PV = nRT

where,

P = Pressure of the gaseous mixture = 1.00 atm

V = Volume of the gaseous mixture = 24.62 L

n = number of moles of the gaseous mixture = ?

R = Gas constant = $0.0821\text{ L atm }mol^{-1}K^{-1}$

T = Temperature of the gaseous mixture = 300 K

Putting values in above equation, we get:

$1.00atm\times 24.62L=n_{mix}\times 0.0821\text{ L atm }mol^{-1}K^{-1}\times 300K\\\\n_{mix}=\frac{1.00\times 24.62}{0.0821\times 300}=0.9996mol$

We are given:

Total mass of the mixture = 13.22 grams

Let the mass of nitrogen gas be 'x' grams and that of hydrogen gas be '(13.22 - x)' grams

To calculate the number of moles, we use the equation:

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

For nitrogen gas:

Molar mass of nitrogen gas = 28 g/mol

$\text{Moles of nitrogen gas}=\frac{x}{28}mol$

For hydrogen gas:

Molar mass of hydrogen gas = 2 g/mol

$\text{Moles of hydrogen gas}=\frac{(13.22-x)}{2}mol$

Equating the moles of the individual gases to the moles of mixture:

$0.9996=\frac{x}{28}+\frac{(13.22-x)}{2}\\\\x=12.084g$

To calculate the mass percentage of substance in mixture we use the equation:

$\text{Mass percent of substance}=\frac{\text{Mass of substance}}{\text{Mass of mixture}}\times 100$

Mass of the mixture = 13.22 g

For nitrogen gas:

Mass of nitrogen gas = x = 12.084 g

Putting values in above equation, we get:

$\text{Mass percent of nitrogen gas}=\frac{12.084g}{13.22g}\times 100=91.41\%$

For hydrogen gas:

Mass of hydrogen gas = (13.22 - x) = (13.22 - 12.084) g = 1.136 g

Putting values in above equation, we get:

$\text{Mass percent of hydrogen gas}=\frac{1.136g}{13.22g}\times 100=8.59\%$

Hence, the mass percent of nitrogen gas and hydrogen gas is 91.41 % and 8.59 % respectively.

5 0

3 years ago

Which statement best explains the net transfer of energy that is about to

ArbitrLikvidat [17]

Answer:

Explanation:

B I got it right

8 0

3 years ago

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Write the complete balanced equation for the decomposition of AI(CIO3)3.

OlgaM077 [116]

Answer:

2AL(ClO3)3 → 2ALCl3 + 9O2

Explanation:

3 0

2 years ago

If you have 6.25g of O2, how many moles of H2O are produced?

denis23 [38]

Answer:

0.4 moles of water produced by 6.25 g of oxygen.

Explanation:

Given data:

Mass of oxygen = 6.25 g

Moles of water produced = ?

Solution:

Chemical equation;

2H₂ + O₂ → 2H₂O

Number of moles of oxygen:

Number of moles = mass/ molar mass

Number of moles = 6.35 g/ 32 g/mol

Number of moles = 0.2 mol

Now we will compare the moles of oxygen with water:

O₂ : H₂O

1 : 2

0.2 : 2×0.2 = 0.4 mol

0.4 moles of water produced by 6.25 g of oxygen.

8 0

3 years ago

Two steps in a synthesis of the analgesic ibuprofen include a carbonyl condensation reaction, followed by an alkylation reaction

Tresset [83]

Ibuprofen is synthesized by reacting ethyl 2-(4-isobutylphenyl)acetate with base, the base abstracts the acidic proton and enolate is formed which on reaction with diethyl carbonate generates diethyl 2-(4-isobutylphenyl)malonate (A). diethyl 2-(4-isobutylphenyl)malonate on treatment with Base again looses the acidic proton and forms enolate. The enolate with treatment with Methyl Iodide yields diethyl 2-(4-isobutylphenyl)-2-methylmalonate (B). diethyl 2-(4-isobutylphenyl)-2-methylmalonate on hydrolysis give Ibuprofen.

4 0

3 years ago

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What is called a measurement and does involve a number and unit in chemistry?​

What is called a measurement and does involve a number and unit in chemistry?