Answer:
(a) 0.779 mol Cr₂O₃
(b) 118 g Cr₂O₃
Explanation:
Step 1: Convert 156 g Cr₂S₃ to moles
Cr Molar Mass - 52.00 g/mol × 2 = 104.00 g/mol
S Molar Mass - 32.07 g/mol × 3 = 96.21 g/mol
156 g Cr₂S₃ ÷ 200.21 g/mol = 0.779182 mol Cr₂S₃
Step 2: Find conversion from Cr₂S₃ to Cr₂O₃
1 mol Cr₂S₃ equals 1 mol Cr₂O₃
Step 3: Use Dimensional Analysis
0.779182 mol Cr₂S₃ · 
= 0.779182 mol Cr₂O₃
0.779182 mol Cr₂O₃ ≈ 0.779 mol Cr₂O₃ (3 significant figures)
Step 4: Convert moles to grams
Cr Molar Mass - 52.00 g/mol × 2 = 104.00 g/mol
O Molar Mass - 16.00 g/mol × 3 = 48.00 g/mol
0.779182 mol Cr₂O₃ · 152.00 g/mol = 118.436 g Cr₂O₃
118.436 g Cr₂O₃ ≈ 118 g Cr₂O₃ (3 significant figures)
Answer:There are 18 electrons and 17 protons, so the chlorine atom has become a charged chlorine ion with a charge of negative one (-1). ... When it does, the sodium atom becomes a sodium ion with a charge of positive one (+1). Chlorine, as mentioned above, desperately wants an electron so it can fill its outer electron level.
Answer:
Describe how a sample of copper chloride crystals could be made from copper carbonate and dilute hydrochloric acid. Add excess copper carbonate to hydrochloric acid in a beaker, stirring until there is no further reaction. Filter the mixture to remove the remaining copper carbonate, then heat the remaining solution to the point of crystallisation.
Explanation: Hope this is right.
Answer:
1) D; 2) B
Explanation:
1) <em>Conservation of atoms
</em>
D is correct.
It has four atoms of H and two of O on each side of the reaction arrow.
A. <em>Wrong</em>. It has the same number of H and O on each side, but it has the <em>wrong product</em>. The reaction forms O₂ molecules, not O atoms.
B. <em>Wrong</em>. Atoms are balanced, but the <em>products are incorrect</em>.
C. <em>Wrong</em>. Atoms are balanced, but the <em>reactants are incorrect</em>.
===============
2) <em>Chemical equations
</em>
B is correct.
The atoms are balanced, and the equation shows the correct formulas of the molecules.
A. <em>Wrong</em>. Atoms are balanced, and the formulas are correct, but the equation is <em>not in its simplest form</em>. The coefficients are not in their lowest terms. We must divide every coefficient by six to get the correct equation: H₂ + Cl₂ ⟶ 2HCl.
C. <em>Wrong</em>. The <em>reactants are incorrect</em>, and the equation is <em>not in its lowest terms</em>.
D. <em>Wrong</em>. The <em>reactants are incorrect</em>.
Answer: 252.5 kPa
Explanation:
Given that:
initial volume of gas V1 = 5.00 L
initial pressure of gas P1 = 101 kPa.
new Volume V2 = 2.00 L
new pressure P2 = ?
Since, only pressure and volume are involved, apply the formula for Boyle's law
P1V1 = P2V2
101 kPa x 5.0L = P2 x 2.00L
505 = P2 x 2.00L
P2 = 505/2.00
P2 = 252.5 kPa
Thus, the new pressure of gas inside the piston is 252.5 kPa
