Explanation:
The atoms are chemically bonded together, and they retain their individual physical and chemical properties.
Answer:
Chemical change
Explanation:
From all indicators, Aurelia is seeing a chemical change occurring in the reaction here.
A chemical change is a change in which new substances are produced. For every chemical change:
- they are not easily reversible
- they lead to production of new kinds of substances
- involves mass change
- require considerable amount of energy.
We start off and end with:
Metal + Acid → Black metal + rising gaseous bubbles
Clearly, it is shown that new products are formed and this reaction is impossible to reverse in order to get the reactants back.
This is a typical chemical change.
Answer:
<u>1. Net ionic equation:</u>
- Cl⁻(aq) + Ag⁺(aq) → AgCl(s)
<u />
<u>2. Volume of 1.0M AgNO₃</u>
Explanation:
1. Net ionic equation for the reaction of NaCl with AgNO₃.
i) Molecular equation:
It is important to show the phases:
- (aq) for ions in aqueous solution
- (s) for solid compounds or elements
- (g) for gaseous compounds or elements
- NaCl(aq) + AgNO₃(aq) → AgCl(s) + NaNO₃(aq)
ii) Dissociation reactions:
Determine the ions formed:
- NaCl(aq) → Na⁺(aq) + Cl⁻(aq)
- AgNO₃(aq) → Ag⁺(aq) + NO₃⁻(aq)
- NaNO₃(aq) → Na⁺(aq) + NO₃⁻(aq)
iii) Total ionic equation:
Substitute the aqueous compounds with the ions determined above:
- Na⁺(aq) + Cl⁻(aq) + Ag⁺(aq) + NO₃⁻(aq) → AgCl(s) + Na⁺(aq) + NO₃⁻(aq)
iv) Net ionic equation
Remove the spectator ions:
- Cl⁻(aq) + Ag⁺(aq) → AgCl(s) ← answer
2. How many mL of 1.0 M AgNO₃ will be required to precipitate 5.84 g of AgCl
i) Determine the number of moles of AgNO₃
The reaction is 1 to 1: 1 mole of AgNO₃ produces 1 mol of AgCl
The number of moles of AgCl is determined using the molar mass:
- number of moles = mass in grams / molar mass
- molar mass of AgCl = 143.32g/mol
- number of moles = 5.84g / (143.32g/mol) = 0.040748 mol
ii) Determine the volume of AgNO₃
- molarity = number of moles of solute / volume of solution in liters
- V = 0.040748mol / (1.0M) = 0.040748 liter
- V = 0.040748liter × 1,000ml / liter = 40.748 ml
Round to two significant figures: 41ml ← answer
Answer: 178.9 g
Explanation:
Density = 
find volume of the cube: (5.80 cm) (5.80 cm) (5.80cm) = 195.112 cm³
1.0 cm³ = 1.0 mL
so 195.112 cm³ = 195.112 mL
plug value into density equation:
0.917 g/mL = (mass) / (195.112 mL)
and solve for mass!
Answer:
<u>So, the right answer is</u>
No. of moles of FeS₂ = 0.25 mole
Explanation:
From the balanced
4 FeS2 + 11 O2 → 2 Fe2O3 + 8 SO2
it is clear that 4 mol FeS₂ react with O₂ to give Fe₂O₃ and 8 mol of SO₂
First, we have to convert mass of SO₂ into No. of moles as following:
SO₂ has molar mass = 64 g/mol
No. of moles of SO₂ = (mass / molar mass) = (32 g / 64 g/mol) = 0.5 mol
we know that
4 mol FeS₂ gives→ 8 mol of SO₂
1 mol FeS₂ gives→ 2 mol of SO₂
??? mol FeS₂ gives→ 0.5 mol of SO₂
No. of moles of FeS₂ = (0.5 mol * 1 mol ) / 2 mol = 0.25 mol
<u>So, the right answer is</u>
No. of moles of FeS₂ = 0.25 mol
