Answer: 178.9 g
Explanation:
Density = 
find volume of the cube: (5.80 cm) (5.80 cm) (5.80cm) = 195.112 cm³
1.0 cm³ = 1.0 mL
so 195.112 cm³ = 195.112 mL
plug value into density equation:
0.917 g/mL = (mass) / (195.112 mL)
and solve for mass!
It can be made true by changing "cannot" to "can".
Answer: The molecular formula will be 
Explanation:
If percentage are given then we are taking total mass is 100 grams.
So, the mass of each element is equal to the percentage given.
Mass of C= 70.6 g
Mass of H = 5.9 g
Mass of O = 23.5 g
Step 1 : convert given masses into moles.
Moles of C =
Moles of H =
Moles of O =
Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.
For C = 
For H = 
For O =
The ratio of C : H: O= 4: 4:1
Hence the empirical formula is 
The empirical weight of
= 4(12)+4(1)+1(16)= 68g.
The molecular weight = 136 g/mole
Now we have to calculate the molecular formula.

The molecular formula will be=
Answer:
3.52g
Explanation:
Zr = 90 g/mol
Si = 28 g/mol
O = 16 g/mol
ZrSiO4 = 90 + 28 + (16* 4) = 182g/mol
Mass = Numberof moles * Molar mass
Mass = 1mol * 182g/mol = 182g
In one mole of ZrSiO4, there are 4 oxygen atoms, hence the mass is given as;
4 * 16 = 64g
Hence, 64g of oxygen is present in 182g of ZrSiO4.
10g would contain x
64 = 182
x = 10
x = ( 10 * 64 ) / 182
x = 640 / 182 = 3.52g
Answer:

Explanation:
The<em> energy of a photon</em>, E, can be calculated with the Planck-Einstein equation:

Where:
- h is Planck's constant 6.626×10⁻³⁴ J.s, and
- f is the frequency of the photon or electromagnetic radiation.
Substituting with your data:

Now multiply by Avogadro's number to obtain the energy of one mole of photons:
