Answer:
The second column on the periodic table of the chemical elements is collectively called the alkaline earth metal group: beryllium, magnesium, calcium, strontium, barium, and radium. Because the outer electron structure in all of these elements is similar, they all have somewhat similar chemical and physical properties.
Explanation:
Oxygen is a chemical element with symbol O and atomic number 8. Classified as a nonmetal, Oxygen is a gas at room temperature.
Answer:
CO + 2H2 = CH3OH
Explanation:
1. Label Each Compound With a Variable
aCO + bH2 = cCH3OH
2. Create a System of Equations, One Per Element
C: 1a + 0b = 1c
O: 1a + 0b = 1c
H: 0a + 2b = 4c
3. Solve For All Variables (using substitution, gauss elimination, or a calculator)
a = 1
b = 2
c = 1
4. Substitute Coefficients and Verify Result
CO + 2H2 = CH3OH
L R
C: 1 1 ✔️
O: 1 1 ✔️
H: 4 4 ✔️
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
