Answer:
A 100-watt light bulb takes 100 seconds to use 10,000 J of electrical energy.
Explanation:
Power refers to the amount of work done (or energy consumed) per unit of time. It is usually measured in watts (W), which is equal to 1 Joules per second (
)
So, by definition, to calculate the power consumed or supplied in a time interval the following expression is used:

where P is the power measured in Watts, W is the work measured in Joules, and t is the time measured in seconds.
In this case:
- P=100 Watt
- W= 10,000 J
- t= ?
Replacing:

Solving:

t=100 seconds
<u><em>
A 100-watt light bulb takes 100 seconds to use 10,000 J of electrical energy.</em></u>
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tell me what to do dudette
Answer:
The United States leads the world with over 260 billion short tons of recoverable coal reserves—28% of total global reserves and 50% more than Russia, which possesses the world's second largest reserves. so the answer would be 28%
Explanation:
Answer:
0.4694 moles of CrCl₃
Explanation:
The balanced equation is:
Cr₂O₃(s) + 3CCl₄(l) → 2CrCl₃(s) + 3COCl₂(aq)
The stoichiometry of the equation is how much moles of the substances must react to form the products, and it's represented by the coefficients of the balanced equation. So, 1 mol of Cr₂O₃ must react with 3 moles of CCl₄ to form 2 moles of CrCl₃ and 3 moles of COCl₂.
The stoichiometry calculus must be on a moles basis. The compounds of interest are Cr₂O₃ and CrCl₃. The molar masses of the elements are:
MCr = 52 g/mol
MCl = 35.5 g/mol
MO = 16 g/mol
So, the molar mass of the Cr₂O₃ is = 2x52 + 3x35.5 = 210.5 g/mol.
The number of moles is the mass divided by the molar mass, so:
n = 49.4/210.5 = 0.2347 mol of Cr₂O₃.
For the stoichiometry:
1 mol of Cr₂O₃ ------------------- 2 moles of CrCl₃
0.2347 mol of Cr₂O₃----------- x
By a simple direct three rule:
x = 0.4694 moles of CrCl₃