Question

1. what is the atomic mass of the hydrogen isotope that contains 2 neutrons? a) 1 b) 4 c) 3 d) 2 e) none of the above true/false. write t if the statement is true and f if the statement is false. 41) in ionic compounds the net positive charge always equals the net negative charge. 42) the name of kno₃ is potassium nitratide. 43) the law of constant composition states: all samples of a given compound have the same proportions of their constituent elements. multiple choice. choose the one alternative that best completes the statement or answers the question. 44) how many of each type of atoms are there in the formula nh₄c₂h₃o₂? a) n = 1, h = 4, c = 2, o = 2 b) n = 4, h = 7, c = 2, o = 2 c) n = 1, h = 7, c = 2, o = 2 d) n = 1, h = 3, c = 2, o = 2 e) none of the above 45) carbon monoxide is considered which of the following? a) molecular compound b) ionic compound c) atomic element d) molecular element e) none of the above 46) what is the formula for an ionic compound made of magnesium and sulfur? a) mg₂s b) mgs c) mg₂s₃ d) mgs₂ e) none of the above 47) what is the oxygen - to - hydrogen mass ratio for h₂o₂? a) 0.125 b) 4 c) 8 d) 16 e) none of the above

Explanation:

Step1: Determine atomic mass of hydrogen isotope

Hydrogen has 1 proton. Atomic mass = number of protons + number of neutrons. Given 2 neutrons and 1 proton, atomic mass = 1+2 = 3. So answer to 40 is C.

Step2: Analyze ionic - compound charge statement

In ionic compounds, to be electrically neutral, the net positive charge must equal the net negative charge. So 41 is T.

Step3: Check compound naming

The name of KNO₃ is potassium nitrate, not potassium nitratide. So 42 is F.

Step4: Recall law of constant composition

The law of constant composition states that all samples of a given compound have the same proportions of their constituent elements. So 43 is T.

Step5: Count atoms in NH₄C₂H₃O₂

N: 1, H: 4 + 3=7, C: 2, O: 2. So 44 is C.

Step6: Classify carbon - monoxide

Carbon monoxide (CO) is made up of two non - metals and is a molecular compound. So 45 is A.

Step7: Determine ionic compound formula

Magnesium has a + 2 charge (Mg²⁺) and sulfur has a - 2 charge (S²⁻). The formula for the ionic compound is MgS. So 46 is B.

Step8: Calculate mass ratio in H₂O₂

The molar mass of H is 1 g/mol and of O is 16 g/mol. In H₂O₂, mass of H = 2×1 = 2 g, mass of O = 2×16 = 32 g. Oxygen - to - hydrogen mass ratio = $\frac{32}{2}$=16. So 47 is D.

Answer:

1. C
2. T
3. F
4. T
5. C
6. A
7. B
8. D