Will someone let me know if I did these correct?
1. Rank the following in order of increasing radius based on their positions on the periodic table: S, S-2, Cl
a. S, S-2, Cl
b. S-2, Cl, S
c. Cl, S, S-2
d. Cl, S-2, S
e. S, Cl, S-2
I believe it's C. Cl, S, S-2
Is that correct, did I do that right?
2. Methane burns in oxygen according to the following equation:
CH4(g) + 2O2(g)----> CO2(g) + 2H2O
What is the mass of CO2 produced when 3.4 grams O2 react according to the above equation?
a. 4.7g
b. 4.9g
c. 2.3g
d. 9.4g
e. 0.74g
I did this and got C. 2.3g, is that correct, did I do that right?
Thanks in advance for the help ;-)
I gave hints at the original post. I think these answers are ok.
To answer your question, let's break down each problem and explain how to solve them.
1. Ranking the elements in order of increasing radius:
To determine the order of increasing atomic radius for S, S-2, and Cl, you need to consider their positions on the periodic table. Elemental radius generally increases as you move down a group and decreases as you move across a period from left to right.
In this case, S and Cl are both in the same period, so you need to compare their positions within the period. Since S is located to the left of Cl, its atomic radius is larger. The S-2 ion is formed by gaining two electrons, which increases the electron-electron repulsion and expands the electron cloud, resulting in a larger radius compared to S.
Based on this information, the correct answer is (d) Cl, S-2, S, which correctly orders the elements from smallest to largest atomic radius.
2. Calculating the mass of CO2 produced:
To find the mass of CO2 produced when 3.4 grams of O2 react, you need to use stoichiometry and the balanced chemical equation provided.
From the balanced equation, you can see that one mole of O2 reacts to produce one mole of CO2. Therefore, to determine the amount of CO2 produced, you need to convert the mass of O2 given (3.4g) into moles, and then convert moles of O2 into moles of CO2 using the stoichiometry.
First, calculate the moles of O2:
moles O2 = mass O2 / molar mass O2
Next, use the stoichiometry of the balanced equation to find moles of CO2:
moles CO2 = moles O2
Finally, convert the moles of CO2 back into grams:
mass CO2 = moles CO2 x molar mass CO2
Using the molar masses of O2 (32 g/mol) and CO2 (44 g/mol), you can substitute the values and calculate the answer.
Calculating this yields:
moles O2 = 3.4g / 32 g/mol = 0.10625 mol O2
moles CO2 = 0.10625 mol O2
mass CO2 = 0.10625 mol x 44 g/mol = 4.67g
Therefore, the correct answer is (a) 4.7g, not option (c) 2.3g.
I hope this helps you understand how to solve these problems. If you have any further questions, feel free to ask!