Question

identify the average atomic masses for the element below. Recall from unit 3, the mass number is the average of ALL of the element's isotopes and it accounts for the protons and neutrons found in the atom's nucleus. It is a decimal number since it is a "weight average" of the masses known. (5 points)
Put responses in the correct input to answer the question. Select a response, navigate to the desired input and insert the response. Responses can be selected and inserted using the space bar, enter key, left mouse button or touchpad. Responses can also be moved by dragging with a mouse.
Manganese, Mn Tin, Sn Bromine, Br Rubidium, Rb Neon, Ne
Question 2
Bromine, Br, is what we call a "molecular element" that must exist as Br2
. Using the mass from the interactive periodic table, calculate the molar mass, of one mole of Br2
. To find the molar mass remember you just locate the mass on the periodic table and find the number of atoms of each element using the subscripts. The subscript will tell you what to multiply by for the final answer. State your final answer in the blank. Please carry your answer out to the tenths place, or one decimal. The units of g/mol are listed for you.(1 point)
g/mol
Question 3
For this question, please select the best answer for the molar mass of tin(II) bromide, SnBr2
You can use the interactive periodic table or your work above to solve this. (1 point)
Responses

159.8 g/mol
159.8 g/mol

118.7 g/mol
118.7 g/mol

317.3 g/mol
317.3 g/mol

278.5 g/mol
278.5 g/mol
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Answer 1

Average atomic masses (g/mol):
- Manganese (Mn): 54.94 g/mol
- Tin (Sn): 118.71 g/mol
- Bromine (Br): 79.90 g/mol
- Rubidium (Rb): 85.47 g/mol
- Neon (Ne): 20.18 g/mol

Question 2 (molar mass of Br2): 159.8 g/mol

Question 3 (molar mass of SnBr2): 278.5 g/mol (select 278.5 g/mol)