Molar mass of (NaOH)

Which process is an example of a physical change?

Lostsunrise [7]

Answer:

The answer is flattening

Explanation:

A physical change is generally something that affects the shape of form of the matter and a chemical change results from a chemical reaction. Flames are caused by chemical reactions, as is rust, and the process of a fruit becoming ripe. Thus, the answer is “flattening”.

4 0

2 years ago

The ph of a solution containing 0.818 M acetic acid (ka1.76*10-5) ans 0.172 M sodium acetate is?

kvasek [131]

Explanation:

It is known that the relation between pH and $pK_{a}$ is as follows.

pH = $pK_{a} + log \frac{[salt]}{[acid]}$

and, $pK_{a} = -log K_{a}$

Hence, first we will calculate the value of $pK_{a}$ as follows.

$pK_{a} = -log K_{a}$

= $-log (1.76 \times 10^{-5}$

= 4.75

Now, we will calculate the value of pH as follows.

pH = $pK_{a} + log \frac{[\text{sodium acetate}]}{\text{acetic acid}}$

= $4.75 + log \frac{0.172}{0.818}$

= 4.75 + (-0.677)

= 4.07

Therefore, we can conclude that the pH of given solution is 4.07.

5 0

3 years ago

What are some double replacement reactions you see every day

Cerrena [4.2K]

Answer:

Sodium Bicarbonate (β-3) + Vinegar
Lead Nitrate + Potassium iodide

Explanation:

Baking Soda and vinegar cause an explosion, in which the bicarbonate and vinegar are replaced by nitrate (∨) and oxide (Ф.) When you combine lead nitrate (Δω) with potassium iron, you also see the ingredients you combined disappear, which shall cause a replace reaction

6 0

2 years ago

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:

4

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:

5

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

2 years ago

Read 2 more answers

During photosynthesis, ________.

ludmilkaskok [199]

Answer:

d. there is a net consumption of water and carbon dioxide

Explanation:

Photosynthesis, is the process whereby light energy is transform into chemical energy by

green plants and other photosynthesis capable organisms . In the process of photosynthesis, light energy is captured by green plants which it uses to convert carbon dioxide water, and minerals into energy-rich organic compounds and oxygen is evolved as a byproduct.

It is a chemical reaction taking place inside a plant, resulting in the production of food for the survival of the plant.

Photosynthesis takes place in the leaves of a plant in the presence of sunlight and.

5 0

2 years ago