(HELP FAST)Which of the following always changes when a substance undergoes a<br> chemical change?

Luda [366]

The maximum mass of anhydrous zinc chloride that could be obtained from the products of the reaction is 8.18 g

<h3>Stoichiometry </h3>

From the question, we are to determine the maximum mass of anhydrous zinc chloride that could be obtained

From the given balanced chemical equation,

ZnO + 2HCl → ZnCl₂ + H₂O

This means 1 mole of ZnO will completely react with 2 moles of HCl to produce 1 mole of ZnCl₂ and 1 mole of H₂O

From the given information

Number of moles of ZnO = 0.0830 mole

Now, we will calculate the number of moles of HCl that is present

Volume of HCl added = 100 cm³ = 0.1 dm³

Concentration of the HCl = 1.20 mol/dm³

Using the formula,

Number of moles = Concentration × Volume

Number of moles of HCl present = 1.20 × 0.1 = 0.120 mole

Since

1 mole of ZnO will completely react with 2 moles of HCl to produce 1 mole of ZnCl₂

Then,

0.06 mole of ZnO will react with the 0.120 mole of HCl to produce 0.06 mole of ZnCl₂

Therefore, maximum number of moles of anhydrous zinc chloride that could be produced is 0.06 mole

Now, for the maximum mass that could be produced

Using the formula,

Mass = Number of moles × Molar mass

Molar mass of ZnCl₂ = 136.286 g/mol

Then,

Mass = 0.06 × 136.286

Mass = 8.17716 g

Mass ≅ 8.18 g

Hence, the maximum mass of anhydrous zinc chloride that could be obtained from the products of the reaction is 8.18 g

Learn more on Stoichiometry here: brainly.com/question/11910892

3 0

2 years ago

Assuming equal concentrations and complete dissociation, rank these aqueous solutions by their freezing points. nh4cl cobr3 k2so

Illusion [34]

Answer: CoBr3 < K2SO4 < NH4 Cl

Justification:

1) The depression of the freezing point of a solution is a colligative property, which means that it depends on the number of particles of solute dissolved.

2) The formula for the depression of freezing point is:

ΔTf = i * Kf * m

Where i is the van't Hoof factor which accounts for the dissociation of the solute.

Kf is the freezing molal constant and only depends on the solvent

m is the molality (molal concentration).

3) Since, you are assuming equal concentrations and complete dissociation of the given solutes, the solute with more ions in the molecular formula will result in the solution with higher depression of the freezing point (lower freezing point).

4) These are the dissociations of the given solutes:

a) NH4 Cl (s) --> NH4(+)(aq) + Cl(-) (aq) => 1 mol --> 2 moles

b) Co Br3 (s) --> Co(3+) (aq) + 3Br(-)(aq) => 1 mol --> 4 moles

c) K2SO4 (s) --> 2K(+) (aq) + SO4 (2-) (aq) => 1 mol --> 3 moles

5) So, the rank of solutions by their freezing points is:

CoBr3 < K2SO4 < NH4 Cl

4 0

3 years ago

Read 2 more answers

An atom of 14 6 c carbon decays by gamma decay which atom is left after the decay

ladessa [460]

Answer is: carbon.

<span>During gamma emission the nucleus emits radiation without changing its composition, if for example have nucleus with six protons and six neutrons (carbon atom) and after gamma decay there is nucleus with six protons and six neutrons.
Gamma rays are the electromagnetic waves with the shortest wavelengths (1 pm), highest frequencies (300 EHz) and highest energy (1,24 MeV).</span>

7 0

3 years ago

Read 2 more answers

Hugh wrote the properties of physical and chemical weathering in the table shown.

Talja [164]

Answer:

I am sure that the C one is correct

6 0

3 years ago

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How many particles would be found in a 89.2 g sample of Na?

julsineya [31]

One mole of a substance contains 6.02 × 10∧23 particles. Thus we first convert 89.2 g to moles. 1 mole of sodium contains 23 g
Hence 89.2 g = 89.2 / 23 g = 3.878 moles
Therefore, 3.878 × 6.02×10∧23 particles= 23.346 × 10∧23 particles
Hence 89.2 g of sodium contains 2.335 ×10∧24 particles

5 0

3 years ago

(HELP FAST)Which of the following always changes when a substance undergoes a chemical change?