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3 years ago

List one reason as to why historical growth has slowed in recent years.

Chemistry

1 answer:

hodyreva [135]3 years ago

4 0

Lower fertility and longer lifespans steadily increased the potential labor force relative to the total population

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Calculate the volume 3.00 moles of a gas will occupy at 24.0˚C and 1.003 atm. *

vitfil [10]

Answer: 72.93 litres

Explanation:

Given that:

Volume of gas (V) = ?

Temperature (T) = 24.0°C

Convert 24.0°C to Kelvin by adding 273

(24.0°C + 273 = 297K)

Pressure (P) = 1.003 atm

Number of moles (n) = 3 moles

Molar gas constant (R) is a constant with a value of 0.0821 atm L K-1 mol-1

Then, apply ideal gas equation

pV = nRT

1.003 atm x V = 3.00 moles x 0.0821 atm L K-1 mol-1 x 297K

1.003 atm•V = 73.15 atm•L

Divide both sides by 1.003 atm

1.003 atm•V/1.003 atm = 73.15 atm•L/1.003 atm

V = 72.93 L

Thus, the volume of the gas is 72.93 litres

5 0

3 years ago

Copper metal (Cu) reacts with silver nitrate (AgNO3) in aqueous solution to form Ag and Cu(NO3)2. An excess of AgNO3 is present.

sweet [91]

Toichiometry time! Remember to look at the equation for your molar ratios in other problems.
31.75 g Cu | 1 mol Cu | 2 mol Ag | 107.9 g Ag 6851.65⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻ → ⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻⁻ = 107.9 g Ag ∅ | 63.5 g Cu | 1 mol Cu | 1 mol Ag 63.5

There's also a shorter way to do this: Notice the molar ratio from Cu to Ag, which is 1:2. When you plug in 31.75 into your molar mass for Cu, it equals 1/2 mol. That also means that you have 1 mol Ag because of the ratio, qhich you can then plug into your molar mass, getting 107.9 as well.

3 0

2 years ago

Read 2 more answers

Describe the motion of molecules in an ice cube and in a radiator in winter

KIM [24]

The motion of molecules in a ice cube are so packed together that they can't move freely like molecules in liquids and gases

8 0

2 years ago

Read 2 more answers

A serving of soup contains 5.0 g of fat, 20.0 g of carbohydrates, and 3.0 g of protein. Determine how many kilocalories (kcal) a

marta [7]

Answer: The amount of kilocalories contained in the given serving of soup is 0.137 kCal

Explanation:

As per the USDA:

Carbohydrates provide 4 calories per gram, protein provides 4 calories per gram, and fat provides 9 calories per gram.

We are given

Mass of fat in the soup serving = 5.0 g

Mass of carbohydrates in the soup serving = 20.0 g

Mass of protein in the soup serving = 3.0 g

Conversion factor used: 1 kCal = 1000 Cal

Applying unitary method:

For Fat:

1 gram of fat provides 9 calories

So, 5.0 gram of fat will provide = $\frac{9}{1}\times 5.0=45Cal=0.045kCal$

For Carbohydrates:

1 gram of carbohydrates provides 4 calories

So, 20.0 gram of carbohydrates will provide = $\frac{4}{1}\times 20.0=80Cal=0.080kCal$

For Proteins:

1 gram of proteins provides 4 calories

So, 3.0 gram of fat will provide = $\frac{4}{1}\times 3=12Cal=0.012kCal$

Total kilocalories per serving = [0.045 + 0.080 + 0.012] kCal = 0.137 kCal

Hence, the amount of kilocalories contained in the given serving of soup is 0.137 kCal

4 0

3 years ago

Calculate the values of ΔU, ΔH, and ΔS for the following process:

ladessa [460]

Answer:

ΔU = 45.814 KJ

ΔH = 46.4375 KJ

ΔS = 18.76 J/K

Explanation:

H2O(l) → H2O(l) → H2O(steam)

298.15K, 1atm ΔHp 373.15K,1atm ΔHv 373.15K,1 atm

∴ ΔHp = Qp = nCpΔT

∴ n H2O = 1 mol

∴ Cp,n = 75.3 J/mol.K

∴ ΔT = 373.25 - 298.15 = 75 K

⇒ Qp = (1 mol)*(75.3 J/mol.K)*(75K) = 5647.5 J

⇒ ΔHp = 5647.5 J = 5.6475 KJ

⇒ ΔH = ΔHp + ΔHv

∴ ΔHv = 40.79 KJ/mol * 1 mol = 40.79 KJ

⇒ ΔH = 5.6475 KJ + 40.79 KJ = 46.4375 KJ

ideal gas:

∴ ΔH = ΔU + PΔV

∴ V1 = nRT1/P1 = ((1)*(0.082)*(298.15))/1 = 24.45 L

∴ V2 = nRT2/P2 = ((1)*(0.082)*(373.15))/ 1 = 30.59 L

⇒ ΔV = V2 - V1 = 6.15 L * (m³/1000L) = 6.15 E-3 m³

∴ P = 1 atm * (Pa/ 9.86923 E-6 atm) = 101325.027 Pa

⇒ ΔU = ΔH - PΔV = 46.4375 KJ - ((101325.027 Pa*6.15 E-3m³)*(KJ/1000J))

⇒ ΔU = 46.4375 KJ - 0.623 KJ

⇒ ΔU = 45.814 KJ

∴ ΔS = Cv,n Ln (T2/T1) + nR Ln (V2/V1)

⇒ ΔS = (75.3) Ln(373.15/298.15) + (1)*(8.314) Ln (30.59/24.45)

⇒ ΔS = 16.896 J/K + 1.863 J/K

⇒ ΔS = 18.76 J/K

3 0

3 years ago