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3 years ago

Which of the following statements is true according to the law of conservation of energy?

2 answers:

8 0

The statement that is true according to the law of conservation of energy is D. all of the above. Energy cannot be created, it already exists everywhere around us. Energy cannot be destroyed, as it will always be present in some form or another. Energy can be converted from one form to another, and thus it will always exist without being destroyed.Hope this helps. Let me know if you need additional help!

ladessa [460]3 years ago

6 0

The best answer out of all of them is
D. All of the above

You might be interested in

When the number of protons and electrons is the same for an atom, the atom is

lawyer [7]

Answer:

A) Neutral.

Explanation:

Protons are positively charged and electrons are negatively charged, while neutrons have no charge. In a "neutral atom", the number of protons must be equal to the number of electrons, otherwise it would not be neutral.

Hope this helps! :)

8 0

4 years ago

1.) Rust forms when Fe, O₂, and H₂O react in the balanced equation below;

valentinak56 [21]

Answer:

1.) A.) The limiting reactant is Fe.

B.) 16.17 g.

2.) 84.70 %.

Explanation:

For the balanced equation:

2Fe(s) + O₂(g) + 2H₂O(l) → 2Fe(OH)₂(s).

2.0 moles of Fe reacts with 1.0 mole of oxygen and 2.0 moles of water to produce 2.0 moles of Fe(OH)₂.

A.) Which of these reactants is the limiting reagent?

To determine the limiting reactant, we should calculate the no. of moles of reactants using the relation: n = mass/molar mass.

Suppose that water is exist in excess.

no. of moles Fe = mass/atomic mass = (10.0 g)/(55.845 g/mol) = 0.179 mol ≅ 0.18 mol.

no. of moles of O₂ = mass/molar mass = (4.0 g)/(32.0 g/mol) = 0.125 mol.

Since from the balanced equation; every 2.0 moles of Fe reacts with 1.0 mole of oxygen.

So, 0.18 mol of Fe reacts with 0.09 mol of O₂.

Thus, the limiting reactant is Fe.

The reactant in excess is O₂ (0.125 mol - 0.09 mol = 0.035 mol).

B.) How many grams of Fe(OH)₂ are formed?

Using cross multiplication:

∵ 2.0 moles of Fe produce → 2.0 moles of Fe(OH)₂.

∴ 0.18 moles of Fe produce → 0.18 moles of Fe(OH)₂.

∴ The mass (no. of grams) of produced 0.18 mol of Fe(OH)₂ = no. of moles x molar mass = (0.18 mol)(89.86 g/mol) = 16.17 g.

2.) (Using the reaction listed in question 1.) If 2.00 g Fe is reacted with an excess of O₂ and H₂0, and a total of 2.74 g of Fe(OH)₂ is actually obtained, what is the % yield?

The % yield = [(actual mass/calculated mass)] x 100.

The actual mass = 2.74 g.

We need to calculate the theoretical mass:

Firstly, we should calculate the no. of moles of reactants using the relation: n = mass/molar mass.

no. of moles Fe = mass/atomic mass = (2.0 g)/(55.845 g/mol) = 0.0358 mol ≅ 0.036 mol.

Using cross multiplication:

∵ 2.0 moles of Fe produce → 2.0 moles of Fe(OH)₂.

∴ 0.036 moles of Fe produce → 0.036 moles of Fe(OH)₂.

∴ The calculated mass (no. of grams) of produced 0.036 mol of Fe(OH)₂ = no. of moles x molar mass = (0.036 mol)(89.86 g/mol) = 3.235 g.

∴ The % yield = [(actual mass/calculated mass)] x 100 = [(2.74 g/3.235 g)] x 100 = 84.70 %.

4 0

4 years ago

PLS PLS HELP DUE TODAY!!

Elina [12.6K]

The answer is D wave 2 has more energy because it has a high frequency than wave one

3 0

3 years ago

Read 2 more answers

Rank the following in order of strength of inter-molecular forces from strongest to weakest:

adoni [48]

Solid is most dense then liquid less dense and more fluid then gas is sort of all over the place so probably solid-liquid-gas

6 0

4 years ago

WILL GIVE 50 POINTS AND BRAINLIEST!!!!!

KATRIN_1 [288]

1. name: cobalt(iii) bromate
formula : Co(BrO)3

2. name: potassium acetate
formula: KC2H3O2

3 0

3 years ago