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3 years ago

3. What is meiosis?

Chemistry

1 answer:

ikadub [295]3 years ago

8 0

Answer:

a type of cell division that results in four daughter cells each with half the number of chromosomes of the parent cell, as in the production of gametes and plant spores.

Explanation:

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Use the graph to answer these questions. For numerical answers, use correct significant digits.

kykrilka [37]

Answer:

1. Letter  A shows the overall enthalpy of reaction

2. which is equal to kJ 2,538.90kJ

3. Letter  B shows the activation energy for the reaction

4. The activated complex is represented by letter C

Explanation:

1. Letter __ shows the overall enthalpy of reaction

The overall enthalpy of reaction is equal to the change of enthalpy of the substances:

Enthalpy of reaction = ∑ enthalpy of the products - ∑enthalply of the reactants.

The products are shown of the right side of the diagram. They are C₆H₁₂O₆(g) and 6O₂(g).

The reactants are shown of the left side of the diagram. They are 6CO₂(g) and 6H₂O(g).

The arrow labeled A shows the difference between the enthalpies of the products and the reactants; thus this shows the overall enthalpy of reaction.

2. which is equal to kJ__

You must subtract the enthalpy of the iniital state (reactants) from the enthalpy of the final state (products).

Overall enthalpy of reaction = - 1,273.02kJ - ( - 3,811.92kJ)

Overall enthalpy of reaction = 2,538.90kJ

This is a positive change indicating the reaction is endothermic.

3. Letter___shows the activation energy for the reaction

The activation energy is the energy that the reactants must gain for the reaction occurs.

Thus, it is the difference between the maximum energy, indicated by the label C on the graph, and initial state.

That is shown by the arrow labeled B: the reactants must gain the amount of energy indicated by the arrow labeled B to reach the energy of the state labeled C.

4. The activated complex is represented by ____

The activated complex is the intermediate compound formed while the reactants are breaking their bonds and new bonds start to form the products. It is also called transition state.

The activated complex is on the top of the energy diagram because it hat the highest energy. The formation of the activated complex always requires energy (it is an endothermic process). Once it is formed, energy is released and the reactants are formed (this part is exothermic).

Thus, the activated complex is labeled with the letter C.

8 0

4 years ago

Read 2 more answers

Many moderately large organic molecules containing basic nitrogen atoms are not very soluble in water as neutral molecules, but

alukav5142 [94]

Answer:

a) For nicotine, the protonated form is the present in stomach.

b) For caffeine, the neutral base form is the present in stomach.

c) For Strychinene, the protonated form is the present in stomach.

d) For quinine, the protonated form is the present in stomach.

Explanation:

In a basic dissociation for molecules with basic nitrogen, the equilibrium is:

A + H₂O ⇄ AH⁺ + OH⁻

Where A is neutral base and AH⁺ is protonated form

The basic dissociation constant, kb, is:

$K_{b} = \frac{[AH^+][OH^-]}{[A]}$

As pH in stomach is 2,5:

[OH] = $10^{-[14-pH]}$

[OH] = 3,16x10⁻¹² M

Thus:

$\frac{K_{b}}{3,16x10^{-12}} =\frac{[AH^+]}{[A]}$ (1)

Using (1) it is possible to know if you have the neutral base or the protonated form, thus:

(a) nicotine Kb = 7x10^-7

$\frac{K_{b}}{3,16x10^{-12}} =\frac{[AH^+]}{[A]}$

$\frac{7x10^{-7}}{3,16x10^{-12}} =\frac{[AH^+]}{[A]}$

$221359 = \frac{[AH^+]}{[A]}$

[AH⁺}>>>>[A]

For nicotine, the protonated form is the present in stomach

(b) caffeine,Kb= 4x10^-14

$\frac{K_{b}}{3,16x10^{-12}} =\frac{[AH^+]}{[A]}$

$\frac{4x10^{-14}}{3,16x10^{-12}} =\frac{[AH^+]}{[A]}$

$0,0127 = \frac{[AH^+]}{[A]}$

[AH⁺}<<<<[A]

For caffeine, the neutral base form is the present in stomach

(c) strychnine Kb= 1x10^-6

$\frac{K_{b}}{3,16x10^{-12}} =\frac{[AH^+]}{[A]}$

$\frac{1x10^{-6}}{3,16x10^{-12}} =\frac{[AH^+]}{[A]}$

$314456 = \frac{[AH^+]}{[A]}$

[AH⁺}>>>>[A]

For Strychinene, the protonated form is the present in stomach

(d) quinine, Kb= 1.1x10^-6

$\frac{K_{b}}{3,16x10^{-12}} =\frac{[AH^+]}{[A]}$

$\frac{1,1x10^{-6}}{3,16x10^{-12}} =\frac{[AH^+]}{[A]}$

$347851= \frac{[AH^+]}{[A]}$

[AH⁺}>>>>[A]

For quinine, the protonated form is the present in stomach.

I hope it helps!

7 0

3 years ago

A 1.0 L sample of an aqueous solution contains 0.10 mol of NaCl and 0.10 mol of CaCl2. What is the minimum number of moles of Ag

Annette [7]

Answer:

The answer to your question is: 0.3 moles of AgNO₃

Explanation:

1.0 L sample

0.1 mol of NaCl

0.1 mol of CaCl₂

AgNO₃ = ? moles

Reactions

NaCl + AgNO₃ ⇒ AgCl + NaNO₃

Then 1 NaCl mol --------------- 1 AgNO₃

0.1 mol -------------- x

x = 0.1 moles of AgNO₃ needed

CaCl₂ + 2 AgNO₃ ⇒ 2 AgCl + Ca(NO₃)₂

Then 1 mol of CaCl₂ ------------- 2 moles of AgNO₃

0.1 mol ------------- x

x = 0.2 moles of AgNO₃

Total moles of AgNO₃ = 0.1 + 0.2 = 0.3

5 0

3 years ago

How many grams of iron (density = 7.87 g/mL ) would occupy the same volume as 96.4 g of aluminum (density = 2.70 g/mL)?

jasenka [17]

Volume of Al:

D = m / V

2.70 = 96.4 / V

V = 96.4 / 2.70 => 35.70 mL

Mass of iron:

D = m / V

7.87 = m / 35.70

m = 7.87 x 35.70 => 280.959 g

hope this helps!

7 0

3 years ago

Read 2 more answers

Scribing the Phases of the Moon

barxatty [35]

Answer:

1, 3, 6

Explanation:

5 0

3 years ago

Read 2 more answers