The chemical process of photosynthesis is one that requires a constant supply of energy to proceed; in this

If the heat released during condensation goes only to warming the iron block, what is the final temperature (in ∘C) of the iron

OLga [1]

Answer:

$91°C$

Explanation:

CHECK THE COMPLETE QUESTION BELOW;

Suppose that 0.95 g of water condenses on a 75.0 g block of iron that is initially at 22 Â°c. if the heat released during condensation is used only to warm the iron block, what is the final temperature (in Â°c) of the iron block? (assume a constant enthalpy of vaporization for water of 44.0 kj/mol.)

Heat capacity which is the amount of heat required to raise the temperature of an object or a substance by one degree

From the question, it was said that that 0.95 g of water condenses on the block thenwe know that Heat evolved during condensation is equal to the heat absorbed by iron block.

Then number of moles =given mass/ molecular mass

Molecular mass of water= 18 g/mol

Given mass= 0.95 g

( 0.95 g/18 g/mol)

= 0.053 moles

Then Heat evolved during condensation = moles of water x Latent heat of vaporization

Q= heat absorbed or released

H=enthalpy of vaporization for water

n= number of moles

Q=nΔH

Q = 0.053 moles x 44.0 kJ/mol

= 2.322 Kj

=2322J

We can now calculate Heat gained by Iron block

Q = mCΔT

m = mass of substance

c = specific heat capacity

=change in temperature

m = 75 g

c = 0.450 J/g/°C

If we substitute into the above formula we have

Q= 75 x 0.450 x ΔT

2322 = 75 x 0.450 x ΔT

ΔT = 68.8°C

Since we know the difference in temperature, we can calculate the final temperature

ΔT = T2 - T1

T1= Initial temperature = 22°C

T2= final temperature

ΔT= change in temperature

T2 = T1+ ΔT

= 68.8 + 22

= 90.8 °C

=91°C

Therefore, final temperature is $91°C$

6 0

3 years ago

Which element among these has the most negative electron affinity (i.e., has most exothermic electron affinity). A. H B. Li C. C

OleMash [197]

Answer:

D. F

Explanation:

Electron affinity is defined as the change in energy (in kJ/mole) of a neutral atom (in the gaseous phase) when an electron is added to the atom to form a negative ion. In other words, the neutral atom's likelihood of gaining an electron.

The electron affinity values of the following elements is given;

Electron Affinity of Hydrogen is 72.8 kJ/mol.

Electron Affinity of Lithium is 59.6 kJ/mol

electron affinity of carbon is 153.9 kJ mol‑1

Electron Affinity of Fluorine is 328 kJ/mol

The electron affinity of neon is 0 kJ mol‑1.

When nonmetals gain electrons, the energy change is usually negative because they give off energy to form an anion (exothermic process); thus, the electron affinity will be negative.

Nonmetals have a higher electron affinity than metals, meaning they are more likely to gain electrons than atoms with a lower electron affinity.

That explains why florine seems to have the highest electron affinity value.

7 0

4 years ago

Using the molecular weight (258 g/mol) determine the amount of mmol of (3S)-2,2,- dibromo-3,4-dimethylpentane required.

Varvara68 [4.7K]

The question is incomplete, the complete question is;

With all of this data in hand, we can now set up our reaction. To begin we are going to use 0.7 g of (35)-2.2-dibromo-3,4-dimethylpentane. Question #7: Using the molecular weight (258 g/mol) determine the amount of mmol of (3S)-2,2,- dibromo-3,4-dimethylpentane required. Round to the tenths place

Answer:

2.70 mmols

Explanation:

Given that;

Mass of (3S)-2,2,- dibromo-3,4-dimethylpentane = 0.7 g

Molar mass of (3S)-2,2,- dibromo-3,4-dimethylpentane = 258 g/mol

From,

Number of moles = mass/molar mass

Number of moles of (3S)-2,2,- dibromo-3,4-dimethylpentane = 0.7g/258 g/mol = 2.7 ×10^-3 moles

Therefore;

Number of moles of (3S)-2,2,- dibromo-3,4-dimethylpentane = 2.70 mmols

8 0

4 years ago

Please help! Thanks!

hram777 [196]

I don’t know really sorry

8 0

4 years ago

Read 2 more answers

A 0.180 mole quantity of NiCl 2 is added to a liter of 1.20 M NH 3 solution. What is the concentration of Ni 2 + ions at equilib

Nutka1998 [239]

Answer:

1.09 x 10⁻⁴ M

Explanation:

The equation of the reaction in given by

Ni²⁺ (aq) + 6NH₃ (aq) ⇔ Ni(NH₃)₆

At the beginning o the reaction, we have 0.18M concentration of Ni and 1.2M concentration of aqueous NH₃ and zero concentration of the product

As the reaction proceeds towards equilibrium, the concentration of the reactants decrease as the concentration of the product starts to increase

From the equation,

1 mole of Ni²⁺ reacts with 6 moles of aqueous NH₃ to give 1mole of Ni(NH3)

therefore

0.18 M of Ni would react with 1.08M (6 x 0.18M) aqueous NH₃ to give 0.18M of Ni(NH₃)6

At equilibrium,

1.08M of NH3 would have reacted to form the product leaving

(1.2 - 1.08)M = 0.12M of aqueous NH₃ left as reactant.

Therefore, formation constant K which is the ratio of the concentration of the product to that of the reactant is given by

K = [Ni(NH₃)₆} / [Ni²⁺] 6[NH₃]

5.5 x 10⁸ = 0.18 M / [Ni²⁺] [0.12]⁶

[Ni²⁺]= 0.18 M / (5.5 x 10⁸) (2.986 x 10⁻⁶)

=0.18 M / 0.00001642

= 1.09 x 10⁻⁴ M

[Ni]²⁺ = 1.09 x 10⁻⁴ M

Hence the concentration of Ni²⁺ is 1.09 x 10⁻⁴ M

4 0

4 years ago