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2 years ago

Which of the following statements is true?

1 answer:

7 0

I believe A.
Calcium and potassium help with blood pressure, muscles, and bones.

For b, there is little helium in the atmosphere.
For C, the center is made of neutrons and protons, electrons are far away.

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What are the sex cells of the plants that Mendel studied?

guajiro [1.7K]

Answer:

alleles

Explanation:

8 0

2 years ago

Read 2 more answers

Calculate ΔrG∘ at 298 K for the following reactions.CO(g)+H2O(g)→H2(g)+CO2(g)2-Predict the effect on ΔrG∘ of lowering the temper

KonstantinChe [14]

Answer:

1) ΔG°r(298 K) = - 28.619 KJ/mol

2) ΔG°r will decrease with decreasing temperature

Explanation:

CO(g) + H2O(g) → H2(g) + CO2(g)

1) ΔG°r = ∑νiΔG°f,i

⇒ ΔG°r(298 K) = ΔG°CO2(g) + ΔG°H2(g) - ΔG°H2O(g) - ΔG°CO(g)

from literature, T = 298 K:

∴ ΔG°CO2(g) = - 394.359 KJ/mol

∴ ΔG°CO(g) = - 137.152 KJ/mol

∴ ΔG°H2(g) = 0 KJ/mol........pure substance

∴ ΔG°H2O(g) = - 228.588 KJ/mol

⇒ ΔG°r(298 K) = - 394.359 KJ/mol + 0 KJ/mol - ( - 228.588 KJ/mol ) - ( - 137.152 KJ7mol )

⇒ ΔG°r(298 K) = - 28.619 KJ/mol

2) K = e∧(-ΔG°/RT)

∴ R = 8.314 E-3 KJ/K.mol

∴ T = 298 K

⇒ K = e∧(-28.619/(8.314 E-3)(298) = 9.624 E-6

⇒ ΔG°r = - RTLnK

If T (↓) ⇒ ΔG°r (↓)

assuming T = 200 K

⇒ ΔG°r(200 K) = - (8.314 E-3)(200)Ln(9.624E-3)

⇒ ΔG°r (200K) = - 19.207 KJ/mol < ΔG°r(298 K) = - 28.619 KJ/mol

6 0

2 years ago

What converts electric energy to radiant energy and thermal energy?

riadik2000 [5.3K]

Answer:

Many things, but i think a toaster...

Explanation:

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2 years ago

How many grams of h2 will be produced if 175g of HCI are allowed to react completely with sodium

Sedbober [7]

Answer:

4.8 grams of H₂ will be produced if 175g of HCI are allowed to react completely with sodium

Explanation:

By stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction) you can see that the following amounts in moles of each compound react and are produced:

HCl: 2 moles
Na: 1 mole
NaCl: 2 moles
H₂: 1 mole

You know the following masses of each element:

H: 1 g/mole
Cl: 35.45 g/mole
Na: 23 g/mole

So, the molar mass of each compound participating in the reaction is:

HCl: 1 g/mole + 35.45 g/mole= 36.45 g/mole
Na: 23 g/mole
NaCl: 23 g/mole + 35.45 g/mole= 58.45 g/mole
H₂: 2* 1 g/mole= 2 g/mole

Then, by stoichiometry of the reaction, the following amounts in grams of each of the compounds participating in the reaction react and are produced:

HCl: 2 moles* 36.45 g/mole= 72.9 g
Na: 1 mole* 23 g/mole= 23 g
NaCl: 2 moles* 58.45 g/mole= 116.9 g
H₂: 1 mole* 2 g/mole= 2 g

So, a rule of three applies as follows: if by stoichiometry, when reacting 72.9 grams of HCl 2 grams of H₂ are formed, when reacting 175 grams of HCl how much mass of H₂ will be formed?

$mass of H_{2} =\frac{175 g of HCl*2g ofH_{2} }{72.9 g of HCl}$