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2 years ago

In chemical reactions, atoms are

1 answer:

5 0

<span>In chemical reaction, atoms always are rearranged. They are never destroyed or created because it would contradict the law of conservation of energy. The law of conservation of energy states that a matter cannot be created nor destroyed. It can only be formed in one way or the other. Also it cannot be neutralized. Resulting in one cannot be part of a chemical reaction. An example of this is the reaction HCl + NaOH -> NaCl + H2O. the reactants and products are not created, they are just formed into another substance.</span>

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Identify the basic structure of a chemical equation?

antiseptic1488 [7]

It is the crust, the least dense layer.

3 0

3 years ago

.ASAPPP

kati45 [8]

Answer:

Explanation:

5 0

2 years ago

A solution may contain Ag+, Pb2+, and/or Hg22+. A white precipitate forms when 6 M HCl is added. The precipitate is partially so

omeli [17]

Answer:

All three are present

Explanation:

Addition of 6 M HCl would form precipitates of all the three cations, since the chlorides of these cations are insoluble: $AgCl (s), PbCl_2 (s), Hg_2Cl_2 (s)$ .

Firstly, the solid produced is partially soluble in hot water. Remember that out of all the three solids, lead(II) choride is the most soluble. It would easily completely dissolve in hot water. This is how we separate it from the remaining precipitate. Therefore, we know that we have lead(II) cations present, as the two remaining chlorides are insoluble even at high temperatures.
Secondly, addition of liquid ammonia would form a precipitate with silver: $AgCl (s) + 2 NH_3 (aq) + H_2O (l)\rightarrow [Ag(NH_3)_2]OH (s) + HCl (aq)$ ; Silver hydroxide at higher temperatures decomposes into black silver oxide: $2 [Ag(NH_3)_2]OH (s)\rightarrow Ag_2O (s) + H_2O (l) + 4 NH_3 (g)$ .
Thirdly, we also know we have $Hg_2^{2+}$ in the mixture, since addition of potassium chromate produces a yellow precipitate: $Hg_2^{2+} (aq) + CrO_4^{2-} (aq)\rightarrow Hg_2CrO_4 (s)$ . The latter precipitate is yellow.

3 0

3 years ago

Jayden says that the dentist can shine a special light on his teeth that will make his teeth become whiter. Can light change Jay

arsen [322]

Answer:

Explanation:

This is because light cannot not whiten Jayden's teeth but light can change materials by hearing it up. There are some substances or tooth paste that can be use to whiten the teeth because of the content they are made off which whitens the teeth. Some of it include baking soda, hydrogen peroxide toothpaste, tumeric toothpaste, toothpaste that contain fluoride.

5 0

3 years ago

Using the thermodynamic information in the ALEKS Data tab, calculate the standard reaction entropy of the following chemical rea

Lapatulllka [165]

Answer:

-122 J/K

Explanation:

Let's consider the following balanced reaction.

N₂(g) + 2 O₂(g) ⇒ 2 NO₂(g)

We can calculate the standard reaction entropy (ΔS°) using the following expression.

ΔS° = Σ ηp × Sf°p - Σ ηr × Sf°r

where,

η: stoichiometric coefficients of products and reactants

Sf°r: entropies of formation of products and reactants

ΔS° = 2 mol × 240.06 J/K.mol - 1 mol × 191.61 J/K.mol - 2 mol × 205.14 J/K.mol

ΔS° = -121.77 J/K ≈ -122 J/K

8 0

2 years ago