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3 years ago

Please help fast, I will give brainliest!

Chemistry

2 answers:

miss Akunina [59]3 years ago

4 0

I think it’s 20 mol
Sorry if I’m wrong

gulaghasi [49]3 years ago

3 0

I would say that the answer is 20

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A mixture of carbon dioxide and hydrogen gases is maintained in a 6.68 L flask at a pressure of 2.14 atm and a temperature of 19

matrenka [14]

Answer:

The mass of hydrogen gas in the mixture: w₂ = 0.433 g

Explanation:

According to the ideal gas equation:

for an ideal gas, $P.V = n_{total}.R.T$

and $n_{total}= n_{1}+n_{2}$

Here, P: total pressure of the gases = 2.14 atm

V: total volume of the gases = 6.68 L

T: temperature = 19 °C = 19+273.15 = 292.15K (∵ 0°C = 273.15K)

R: gas constant = 0.08206 L·atm·K⁻¹·mol⁻¹

$n_{total}$ : total number of moles of gases

To calculate the total number of moles of gases:

$n_{total} = \frac{P.V}{R.T} = \frac{2.14 atm\times 6.68 L}{0.08206 LatmK^{-}mol^{-}\times 292.15K}$ = 0.5963 moles

Let, the number of moles of carbon dioxide be n₁ and number of moles of hydrogen be n₂

Given: mass of carbon dioxide: w₁ = 16.8 g, mass of hydrogen: w₂ = ?g

molar mass of carbon dioxide: m₁ = 44.01 g/mol, molar mass of hydrogen: m₂= 2.016 g/mol

Therefore, $n_{total}$ = n_{1}+n_{2} = (w₁ ÷ m₁) + (w₂ ÷ m₂)

⇒ 0.5963 mol = (16.8 g ÷ 44.01 g/mol) + (w₂ ÷ 2.016 g/mol)

⇒ 0.5963 mol = (0.3817mol) + (w₂ ÷ 2.016 g/mol)

⇒ 0.5963 mol - 0.3817mol = (w₂ ÷ 2.016 g/mol)

⇒ 0.2146 mol = (w₂ ÷ 2.016 g/mol)

⇒ w₂ = 0.433 g

Therefore, the mass of hydrogen gas in the mixture: w₂ = 0.433 g

4 0

4 years ago

The yogurt bacteria are usually Gram-positive, which means the Gram staining process dyes them ________.

ale4655 [162]

Answer:

The staining process will dye them purple (option C)

Explanation:

Gram staining is a method of staining used to distinguish and classify bacterial species into two large groups. Those 2 groups are called Gram- positive and gram - negative groups.

This staining is based on the composition of their cell wall. Gram staining uses crystal violet to stain cell walls, iodine as a mordant, and a fuchsin or safranin counterstain to mark all bacteria.

⇒ Gram- positive bacteria are called gram - positive because they will give a positive result. This according to their cell wand. Their cell wall is typically rich with peptidoglycan and lacks the secondary membrane and lipopolysaccharide layer found in Gram-negative bacteria

Gram- positive bacteria take up the crystal violet stain used in the test, and then appear to be purple-coloured.

⇒ Gram- negative bacteria are called gram - negative because they will give a negative gram result.

Because of the presence of higher lipid content, after the alcohol-treatment, the porosity of the cell wall increases, hence the CVI complex (crystal violet – iodine) can pass through. Thus, the primary stain (crystal violet) is not retained. Gram negative bacteria will appear red or pink.

Yogurt is produced using a culture of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus bacteria. (In addition, other lactobacilli and bifidobacteria). All of those bacteria are gram-positive, what means they will appear purple.

8 0

4 years ago

Which of the following processes are exothermic and which are endothermic?

suter [353]

Endothermic reactions are reactions that proceed by the absorption of heat (energy) while exothermic reactions involve a release of energy.

a) Formation of frost on a car window in winter is an exothermic process as heat is liberated when liquid water freezes to form crystals

b) Formation of water condensate on a glass of ice water is an endothermic reaction since heat is absorbed by the cold water from the glass container thereby cooling it.

c) A decrease in the temperature as ammonium nitrate is added to water is an endothermic reaction

7 0

3 years ago

Read 2 more answers

This type of triglyceride contains more than one double bond in the fatty acid carbon atoms

erastova [34]

polyunsaturated!!! Hope this helps mark this the brainliest!

4 0

3 years ago

Water has a density of 1g/ml. what is the mass of the water if it fills a 10ml container?

notka56 [123]

It's 10.
Mass = density x volume
M = 1g/ml(10ml) = 10g