solution:
You need to find the frequency, and they have already given you the wavelength. And since you already know the speed of light, you can use formula (2) to answer this problem. Remember to convert the nano meters to meters because the speed of light is in meters. 
Answer:
44.01 g/mol
Explanation:
Add each elements atomic mass. For oxygen you will do that twice because their is two oxygens.
- Hope that helps! Please let me know if you need further explanation.
Answer:
The answer to your question is: 6.8 g of water
Explanation:
Data
2.6 moles of HCl
1.4 moles of Ca(OH)2
2HCl + Ca(OH)2 → 2H2O + CaCl2
MW 2(36.5) 74 36 g 111 g
73g
1 mol of HCl ---------------- 36.5 g
2.6 mol -------------- x
x = (2.6 x 36.5) / 1 = 94.9 g
1 mol of Ca(OH)2 -------------- 74 g
1.4 mol --------------- x
x = (1.4 x 74) / 1 = 103.6 g
Grams of water
73 g of HCl ------------------ 36g of H2O
94.9 g ------------------- x
x = (94.9 x 36) / 73 = 46.8 g of water
they are male
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Answer: NH3
Explanation: N2 + H2 yields NH3.
