Answer:

Explanation:
We know that the speed of light is equal to 
We need to find how far the light travel in 3 days.
Speed of an object is equal to distance covered divided by time taken.
Also, 1 day = 86400 s
3 days = 259200 s
So,


So, the light will travel
in 3 days.
Answer:
2.5 moles of N₂ and 7.5 moles of H₂ entered the reaction
Explanation:
In reaction:
N₂(g) + 3 H₂(g) → 2 NH₃(g)
You can see that the stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction) requires the following amounts of reagents and are produced:
- N₂: 1 mole
- H₂: 3 moles
- NH₃: 2 moles
The following three rules can apply:
- If 2 moles of NH₃ are produced from 1 mole of N₂ by stoichiometry of the reaction, 5 moles of NH₃ from how many moles of N₂ are produced?

moles of N₂= 2.5
- If 2 moles of NH₃ are produced from 3 moles of H₂ by stoichiometry of the reaction, 5 moles of NH₃ from how many moles of H₂ are produced?

moles of H₂= 7.5
<u><em>2.5 moles of N₂ and 7.5 moles of H₂ entered the reaction</em></u>
Answer:
20.9%
Explanation:
- The percentage by mass of solution is given by dividing the mass of solute in grams by the mass of solution in grams then multiplying it by 100%.
% Mass of solution = mass of solute/mass of solution × 100%
= (27.0 g/ 129.0 g) × 100%
= 20.93%
= 20.9%
Answer:
The answer is 5 mol
Explanation:
Number Of Moles = Mass Of Substance ÷ Mass Of One Mole
Mass of NaOH = Molar Mass of Sodium + Oxygen + Hydrogen
23 + 16 + 1
40 g/mol
Number of Mole = 200/40 = 5 mol
Thus, The number of Moles in 200 grams of Sodium hydroxide is 5 mol
<u>-TheUnknownScientist 72</u>
Epsom salt is MgSO4.
We assume x water of hydration in the crystalline form.
Molecular mass of MgSO4 = 24+32+4*16=120
Molecular mass of MgSO4.xH2O = 120+18x
By proportion,
2.000/0.977 = (120+18x)/120
Cross multiply
0.977(120+18x) = 120*2.000
from which we solve for x
17.586x+117.24 = 240
x=122.78/17.586
=6.980
Answer: there are 7 water of hydration in Epsom salt, according to the experiment.
Note: more accurate (proper) results may be obtained by using exact values (3-4 significant figures) in the molecular masses. However, since water of hydration is the nearest integer, using approximate values (to at least two significant figures) suffice.