54 would be the correct answer i beleive
Hope I helped with the answer to your question ;)
I believe the best answer is D.
All answers contribute to a machine, if there is an all above choice, chose that.
Answer:
TRUE
Explanation:
The total length of the wires will affect the amount of resistance. The longer the wire, the more resistance that there will be.
Answer:
227 mL KBr
Explanation:
To find the amount of milliliters KBr, you need to (1) convert grams to moles (via molar mass from values on periodic table), then (2) find the amount of liters KBr (via molarity equation using molarity and moles), and then (3) convert liters to milliliters. The final answer should have 3 sig figs to match the amount of sig figs in the given values.
<u>(Step 1)</u>
Molar Mass (KBr): 39.098 g/mol + 79.904 g/mol
Molar Mass (KBr): 119.002 g/mol
17.2 grams KBr 1 mole
----------------------- x ------------------ = 0.145 moles KBr
119.002 g
<u>(Step 2)</u>
Molarity (M) = moles / volume (L)
0.640 M = 0.145 moles / volume
(0.640 M) x (volume) = 0.145 moles
volume = (0.145 moles) / (0.640 M)
volume = 0.227 L
<u></u>
<u>(Step 3)</u>
<u></u>
0.227 L KBr 1,000 mL
------------------ x ----------------- = 227 mL KBr
1 L
