How
much heat must be added to
85g
of water
to raise its temperature 225?

Answer:

The number following the name of the element is the number of subatomic particles inside the nucleus of the atom. This means that it is the mass number of the isotope. The average atomic mass of the element is the sum of the products of the percentage abundance and mass number of the naturally occurring isotopes.

Since, the average atomic mass of the hydrogen is nearest to 1 then, the most abundant isotope should be hydrogen-1.

Explanation:

The question involves converting from one unit (Kilometres) to another unit (Astronomical unit)

The relationship between both units is given as;

1 Km = 6.68459e-9 Au

Kulper belt

6.5 billion km = 6.5e9 Km

1 Km = 6.68459e-9 Au

6.5e9 Km = x

Solving for x;

x = 43.45 Au

Alpha Centauri

44 trillion km = 4.4e13

1 Km = 6.68459e-9 Au

4.4e13 km = x

Solving for x;

x = 294121.83 Au

Answer:

7.63 × 10²³ molecules

Explanation:

First, convert grams to moles using the molar mass of water (32.988 g/mol).

41.8 g  ÷  32.988 g/mol  =  1.267 mol

Next, convert moles to molecules using Avogadro's number (6.022 × 10²³).

1.267 mol  ×  6.022 × 10²³ molecules/mol = 7.63 × 10²³ molecules

Answer:

a: 6 moles

b: 6.75 moles

c: 5 grams

Explanation:

a: mole ratio 2:3

b: mole ratio 2:3

c: mole ratio 2:2

Answer:

A force meter

Answer:

1. A. 9 eggs

2. B. 5:3

3. C. Exactly 44 g

4. C. Mass and atoms only

5. D. 6.81 g of PH₃

6. C. 88.4%

7. B. O₂

8. D. 30.8 g CO₂

9. B.

10. B.

11. C. 99 g

12. D. mole ratio

13. C. Theoretical

14. A. 6.0 mol H₂O

15. D. 39.7 g CH₃OH

16. A. 650 g HgO

17. D. 8.8 mol H₂

18. B. 82.6%

Explanation:

1. The number of eggs it takes to make 1 cake = 3 eggs

The number of eggs it takes to make 3 × 1 = 3 cake = 3 × 3 = 9 eggs

Therefore, the correct option is;

A. 9 eggs

2. The given reaction is presented as follows;

C₃H₈(g) + 5O₂(g) → 3CO₂(g) + 4H₂O(l)

In the above reaction, we have;

Moles of , O₂, reacted = 5 moles

Moles of , CO₂, produced = 3 moles

The ratio of the of O₂ reacted to moles of CO₂ produced = 5 moles:3 moles

∴ The ratio of the of O₂ reacted to moles of CO₂ produced = 5:3

The correct option is;

B. 5:3

3. The reaction is presented as follows;

O₂ (g) + C(s) → CO₂ (g)

From the reaction, 1 mole (12 g) of carbon produces 1 mole of CO₂

The molar mass of CO₂ = The mass of 1 mole of CO₂ = 44.01 g/mol

Given that the reaction is completed, the mass of CO₂ produced = The mass of 1 mole of CO₂ ≈ 44 g

The correct option is;

C. Exactly 44 g

4. The given reaction is presented as follows;

N₂ + 3 F₂ → 2NF₃

The initial number of atom = 2 + 6 = 8

The final number of atom = 2 × 4   = 8

∴ The initial number of atom = The final number of atom

Therefore, the number of atoms is conserved;

The mass of the reactants ≈ 28 g/mol + 3 × 37.996806 g/mol ≈ 141.993612 g/mol ≈ 142 g/mol

The mass of the product ≈ 2 × 71 g.mol = 142 g/mol

∴ The mass is conserved

Moles of reactants = 1 + 3 = 4

Moles of products = 2

∴ The number of moles is not conserved

The correct option is

C. Mass and atoms only

5. The molar mass of P₄ = 123.895048 g/mol

One mole of P₄ (123.895048 g) produces four moles (4 × 34.00) of PH₃

6.20 g of P₄. will produce (4 × 34.00)/(123.895048) × 6.20 g ≈ 6.80576 g ≈ 6.81 g

The correct option is D. 6.81 g of PH₃

6. The percentage yield = ((The actual yield)/(The ideal yield)) × 100

The actual yield of silver = 38.1 g

The ideal yield of silver = 43.1 g

∴ The percentage yield = ((38.1 g)/(43.1 g)) × 100 = 88.3990719258% ≈ 88.4%

The percentage yield = 88.4%

The correct option is C. 88.4%

7. The given chemical equation is presented as follows;

CS₂ (g) + 3 O₂ (g) → CO₂ (g) + 2 SO₂ (g)

The number of moles in 192 g of O₂ = 192 g/(32 g/mol) = 6 moles

Given that 3 moles of O₂ reacts with 1 mole of CS₂ to produce 1 mole of CO₂ and 2 moles SO₂,  therefore 2 × 3 = 6 moles of O₂ will reacts with 2 × 1 = 2 moles of CS₂ to produce 2 moles of CO₂ and 4 moles SO₂

∴ The limiting reactant is;

B. O₂

8. The given chemical equation is presented as follows;

2 C₈H₁₈ (g) + 25 O₂ (g) → 16 CO₂ (g) + 18 H₂O (l)

The number of moles in 10 g of C₈H₁₈, n₁ = (10 g)/(114.26 g/mol)

The number of moles of CO₂ produced, n₂ = (10 g)/(114.26 g/mol) × 16/2 ≈ 0.7 moles

The mass of CO₂ produced, m ≈ 44.01 × n₂ ≈ 44.01 g/mol × 0.7 moles ≈ 30.807 grams ≈ 30.8 grams

The theoretical yield of CO₂ from completely burning 10.0 g of C₈H₁₈ ≈ 30.8 grams of CO₂

The correct option is D. 30.8 g CO₂

9. The correct option is B. The limiting reactants determine the maximum amount of product that can be formed

10. Option B, which has 3 atoms of each element combining to form a product with 1 atom of one element and 2 atoms of the other element

The correct option is B.

11. By the conservation of mass, we have;

The mass of the reactants = The mass of the products

Let 'x' represent the mass of zinc in the products of the reaction

Therefore, we have;

61 g of calcium + 207 g of zinc chloride = 169 g of calcium chloride + x g of Zinc

∴  x g = 61 g + 207 g - 169 g = 99 g

The mass of zinc in the products of the reaction, x g = 99 g

The correct option is;

C. 99 g

12. The quantity that must be used to convert from one chemical substance to another is the mole ratio

The correct option is D. mole ratio

13. The maximum mass of the product that could form in a reaction is called the theoretical yield, which is option C.

The correct option is C. Theoretical

14. 1 mole of O₂ produces 2 moles of water (H₂O), therefore;

3 × 1 = 3.0 moles of O₂ will produce 3 × 2 = 6 moles of H₂O

The correct option is

A. 6.0 mol H₂O

15. 2 mole × 2.02 g/mol = 4.04 g of H₂ (g) produces 32.05 g CH₃OH (l)

∴ 5 g of H₂ (g) will produce 32.05 g × 5/4.04 ≈ 39.6658416 g ≈ 39.7 g of CH₃OH

The correct option is;

D. 39.7 g CH₃OH

16. 2 (2 × 216.59 g = 433.18 g) moles of HgO produces 1 mole of O₂

1.5 mole of O₂ will be produced by 1.5 × 2 = 3 moles (3 × 216.59 g = 649.77 g ≈ 650 g) of HgO

The correct option is A 650 g HgO

17. 3 moles of H₂ produces 2 moles of NH₃

The number of moles of NH₃ in 100 g of NH₃, n = 100 g/(17.04 g/mol) = 5.868544 moles

The number of moles of H₂ that will produce 5.868544 moles of NH₃ = 3/2 × 5.868544 moles = 8.802816 moles ≈ 8.8 moles

Therefore, the correct option is;

D. 8.8 mol H₂

18. The theoretical yield of PbO = (223.2/331.2) × 9.90 g = 6.67173913 g

The percentage yield = (5.51 g)/(6.67173913 g) × 100 ≈ 82.6%

The correct option is option B 82.6%.

Answer:

KCrO₃

Explanation:

26.6% K, 35.3% Cr and 33.0% O

The steps in obtaining the empirical formulae from percentage composition is given as;

Step 1:

Divide the percentage composition by the atomic mass of the elements

K = 26.6 / 39.0983  = 0.6803

Cr = 35.3 / 51.9961 = 0.6789

O = 33.0 / 16  = 2.0625

Step 2:

Divide all though by the smallest number (0.6789)

K = 0.6803 / 0.6789 = 1.002

Cr = 0.6789 / 0.6789 = 1

O = 2.0625 / 0.6789 = 3.038

The Empirical formular is the ratio between the elements. This given as;

KCrO₃

Answer: C - Organisms return water to the environment after they use it.

Explanation: The amount of water on earth will always remain the same. Water goes in and out of all organisms. It is not possible to be more or less.

Answer:

all of they above

Explanation:

Answer:

(K) = [H2] [Cl2]  /  [HCl]²

Explanation:

The equation of the reaction is given as;

2 HCl (g)  ⇔ H2 (g) + Cl2 (g)

The Equilibrium constant is the ratio of the concentration of the products and reactants raised to the power of their coefficients

Products =  H2 and Cl2

Reactants =  HCl

Equilibrium constant (K) = [H2] [Cl2]  /  [HCl]²

Answer:

In the ring of fire

Hope this acc helps

Answer:

3.79 moles

Explanation:

To convert moles to gams of a substance we need to find the molar mass of the substance. For Ca(OH)₂ th molar mass is:

1Ca = 40.08g/mol

2O = 2*16g/mol = 32g/mol

2H = 2*1.01g/mol = 2.02g/mol

The molar mass is:

40.08g/mol + 32g/mol + 2.02g/mol = 74.1g/mol

And moles are:

281g * (1mol / 74.1g) =

Answer:

linear angleee

Explanation:

lol i dont know what to put here

Answer:

B) Bent

There are a lot of types of bents but this one is linear bent.

Answer:

Anhydrous sodium carbonate is stable to heat and does not decompose even when it is heated to redness. This is because sodium carbonate salt on heating with acids react to release carbon dioxide.

Answer:

the veins and arteries are the things that distribute blood throughout your body. There was a lot more blood in the arteries, that's making them very important and should not be cut ever. Veins on the other hand can be cut but you should still not cut them to begin with as if to not lose any blood. They distribute blood throughout your body that comes from your heart and helps muscles skeletal another systems of your body work.

This should hopefully help

2H³PO⁴ --> H⁴P²O⁷ + H²O

Answer:

Usually, the cells are round, elongated or spherical. There are also some cells which are long and pointed on both the ends. Such cells exhibit spindle shape. In some cases, the cells are very long.

Explanation:

Hope I helped! Brainliest plz!

Answer:

Explanation:

This can be fixed by multiplying the product contacting nitrogen by 2. o The new chemical equation is N2 +H2 →2 NH3. Reactants. Products. Nitrogen. 2. 2.

Answer:

C. do not touch the victim keep the victim quiet and call dor medical assistance

Answer:

D.

Explanation:

MSDS if available should have tx instructions once a call for emergency medical assistance has been made

Answer:

Yes, since it has alcohol, it conducts electricity.