Answer:
The solutions are ordered by this way (from lowest to highest freezing point): K₃PO₄ < CaCl₂ < NaI < glucose
Option d, b, a and c
Explanation:
Colligative property: Freezing point depression
The formula is: ΔT = Kf . m . i
ΔT = Freezing T° of pure solvent - Freezing T° of solution
We need to determine the i, which is the numbers of ions dissolved. It is also called the Van't Hoff factor.
Option d, which is glucose is non electrolyte so the i = 1
a. NaI → Na⁺ + I⁻ i =2
b. CaCl₂ → Ca²⁺ + 2Cl⁻ i =3
c. K₃PO₄ → 3K⁺ + PO₄⁻³ i=4
Potassium phosphate will have the lowest freezing point, then we have the calcium chloride, the sodium iodide and at the end, glucose.
Answer: the percent composition of carbon in heptane is 83.9%
Explanation:
<u>1) Atomic masses of the atoms:</u>
<u>2) Molar mass of heptane:</u>
- C₇H₁₆: 7 × 12.01 g/mol + 16×1.008 g/mol = 100.2 g/mol
<u>3) Mass of carbon in one mole of heptane:</u>
- C₇: 7 × 12.01 g/mol = 84.07 g/mol
<u>3) Percent composition of carbon:</u>
- % = (mass in grams of C) / (mass in grams of C₇H₁₆) × 100 =
= (84.07 g/ 100.2 g) × 100 = 83.9% ← answer
Answer:
Elements can combine in any proportion to form a compound. -third choice
Cesium Sulfite is formed from the Cs cation and the SO₃⁻² anion. The correct formula for this compound is Cs₂SO₃.
<h3>What is Cation ? </h3>
Cations are positively charged ions. It forms when an element lose one or more electrons.
<h3>
What is Anion ? </h3>
Anions are negatively charged ions. It form when an element gains one or more electrons.
Symbol Cs⁺¹ SO₃⁻²
Valency +1 -2
Formula of the compound is Cs₂SO₃.
Thus from the above conclusion we can say that Cesium Sulfite is formed from the Cs cation and the SO₃⁻² anion. The correct formula for this compound is Cs₂SO₃.
Learn more about the Cation and Anions here: brainly.com/question/20005547
#SPJ1