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2 years ago

Dental crown: Uranium-234 is used to make dental crowns appear brighter. The alpha decay of uranium-234 produces what isotope?

Chemistry

1 answer:

Ne4ueva [31]2 years ago

8 0

Answer:

Lithium has two naturally occurring isotopes. Lithium-6 has an atomic mass of 6.015 amu. Lithium-7 has an atomic mass of 7.016 amu. The average atomic mass of lithium is 6.941 amu.

Explanation:

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The reaction converting glycerol to glycerol-3-phosphate (energetically unfavorable) can be coupled with the conversion of ATP t

Brut [27]

Answer:

glycerol-3-phosphate, ADP, H⁺

Explanation:

The reaction of converting glycerol to glycerol-3-phosphate which makes is unfavorable and is coupled with the second reaction which involves conversion of ATP to ADP which is high energetically favorable.

Reaction 1: Glycerol + HPO₄²⁻ ⇒ Glycerol-3-phosphate + water

Reaction 2: ATP + H₂O ⇒ ADP + HPO₄²⁻ + H⁺

The coupled reaction of both the reactions become favorable. Thus, the overall coupled reaction is:

Glycerol + ATP ⇒ Glycerol-3-phosphate + ADP + H⁺

The net products are = glycerol-3-phosphate, ADP, H⁺

8 0

3 years ago

H2CO3(aq) + H200 H30 (aq) + HCO3 (aq).

timofeeve [1]

Answer:

$K_a=\frac{[H_3O^+][HCO_3^-]}{[H_2CO_3]}$

Explanation:

Several rules should be followed to write any equilibrium expression properly. In the context of this problem, we're dealing with an aqueous equilibrium:

an equilibrium constant is, first of all, a fraction;
in the numerator of the fraction, we have a product of the concentrations of our products (right-hand side of the equation);
in the denominator of the fraction, we have a product of the concentrations of our reactants (left-hand side o the equation);
each concentration should be raised to the power of the coefficient in the balanced chemical equation;
only aqueous species and gases are included in the equilibrium constant, solids and liquids are omitted.

Following the guidelines, we will omit liquid water and we will include all the other species in the constant. Each coefficient in the balanced equation is '1', so no powers required. Multiply the concentrations of the two products and divide by the concentration of carbonic acid:

$K_a=\frac{[H_3O^+][HCO_3^-]}{[H_2CO_3]}$

4 0

3 years ago

What is a chemical change and what is a chemical property? Give Example.

nordsb [41]

Look it up on google

8 0

3 years ago

Read 2 more answers

Why is a homogeneous mixture not considered a pure substance? Question 6 options: A pure substance can be separated by physical

krok68 [10]

1. Why is a homogeneous mixture not considered a pure substance?

Answer:

A pure substance can be separated by chemical means, while a mixture can be separated by physical means.

2. What is true if mass is conserved in a reaction?

Answer:

There are equal numbers of atoms on both sides.

3. Methane reacts with oxygen then what are the products?

Answer:

carbon dioxide and water

4. Which one of the following is not a homogeneous mixture?

Answer:

vegetable soup

5. The substance is not uniform in appearance and each part of the mixture contains a combination of different ingredients in different ratios.

Answer:

heterogeneous mixtures

6. If a solution is saturated, which of these is true?

Answer:

More solvent can be dissolved

7. Which of these substances are molecules?

Answer:

All compounds are molecules but not all molecules are compounds. Molecular oxygen (O2) and molecular nitrogen (N2) are not compounds because each is composed of a single element. So correct option is 3 and 4.

8. What makes a solution a homogeneous mixture?

Answer:

It is uniform in composition.

9. When a solute is added to a solution, why does it remain homogeneous?

Answer:

The solute dissolves.

10. The chemical formula of glucose is C6H12O6, so it is classified as a(n)

Answer:

pure substance.

11. How many chlorine (Cl) atoms would be in 4 molecules of salt (4 NaCl)?

Answer:

12. In a solution of salt and water, which component is the solute?

Answer:

Salt

13. These substances are all H2O2, Li , NaCl , O2

Answer:

Pure Substances

14. If you have 5 grams of product after a chemical reaction, how many grams of reactants did you have at the start of the reaction?

Answer:

15. What is the difference between a compound and a mixture?

Answer:

A compound is a pure substance, but a mixture is not.

16. A firework exploding would be an example of a(n) ________.

Answer:

Exothermic reaction

17. If Lavoisier heated 100 grams of powdered mercuric oxide to produce 93 grams of liquid mercury, how much oxygen would be released?

Solution

2HgO ==> 2Hg + O2

Mass of HgO = 100 g

Molar mass of HgO = 216.59 g/mol

Moles = mass/molar mass = 0.46 moles

From balance chemcial equation

HgO : O2

2 = 1

0.46 = (1 × 0.46 ) ÷ 2 = 0.23 moles

mass of O2 = moles× molar mass = 0.23 × 32 = 7.36 g

18. Using the Law of Conservation of Matter, determine the number of grams of iron sulfide (FeS) that will be produced in this reaction.

Solution

12g Fe + 64g S → _____ g FeS

According to Law of Conservation of Matter, The total mass of reactant is equal to total mass of product , so the number of grams of iron sulfide (FeS) that will be produced in this reaction as follow.

12 + 64 = 76 g of FeS

Hope this Help.

3 0

3 years ago

Read 2 more answers

Draw a mechanism for this reaction. 5-hydroxypentanoic acid forms 2-oxanone in the presence of acid. draw all missing reactants

Licemer1 [7]

Answer: -

The first step involves protonation of the carbonyl oxygen.

After protonation, the Alcohol oxygen now attacks the carbon of the carbonyl.

Thus a six membered ring is formed with 5 carbon atoms and 1 oxygen atom. The 1st position carbon atom has 2 OH groups.

One of these gets again protonated.

This leaves as water. With the loss of the H+, there results a carbonyl at 1 position.

Thus 5-hydroxypentanoic acid forms a lactone or 2-oxanone in presence of acid.

3 0

3 years ago