Answer:
=C₄H₄O₂
Explanation:
Given the empirical formula of a molecule, the he the quotient of the molecular mas and and the empirical mass=constant.
84.0 g/mol/mass of(C₂H₂O)=constant
=84/(12×2+1×2×16)
=84/42
=2
Therefore, the molecular formula is (C₂H₂O)₂=C₄H₄O₂
Answer:
Energy, 
Explanation:
It is required to find the energy of an electromagnetic wave with a frequency of
. The energy of a wave in terms of its frequency is given by :

= frequency of em wave

So, the energy of an electromagnetic wave is 
Answer:
A. Do some background research
There are 5 steps for the scientific method while doing an experiment
Step 1: make a question
Step 2: research that question
Step 3: Hypothesis
Step 4: Test and collect data
Step 5: Conclusion
Answer:
0.295 L
Explanation:
It seems your question lacks the final concentration value. But an internet search tells me this might be the complete question:
" A chemist must dilute 47.2 mL of 150. mM aqueous sodium nitrate solution until the concentration falls to 24.0 mM. He'll do this by adding distilled water to the solution until it reaches a certain final volume. Calculate this final volume, in liters. Be sure your answer has the correct number of significant digits. "
Keep in mind that if your value is different, the answer will be different as well. However the methodology will remain the same.
To solve this problem we can<u> use the formula</u> C₁V₁=C₂V₂
Where the subscript 1 refers to the concentrated solution and the subscript 2 to the diluted one.
- 47.2 mL * 150 mM = 24.0 mM * V₂
And <u>converting into L </u>becomes:
- 295 mL *
= 0.295 L