Coal can replace petroleum base fuel when you are just heating something that dont need big amount of heat. examples of it is when producing steam, coal is just used to heat water and produce steam because coal is much cheaper and the coal can already do the job in heating the water
Answer: 193 mg of theobromine are present in the sample.
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number of particles.
To calculate the moles, we use the equation:

1 mole of theobromine
weigh = 180 g
of theobromine
weigh =
(1g=1000mg)
193 mg of theobromine are present in the sample.
Answer:

Explanation:
Data:
MM = 848.952 g/mol
c = 4.0 x 10⁻⁶ g/L
V = 1 L
Calculations:
(a) Mass of growth hormone

(b) Moles of growth hormone

Answer:
The evidence goes against A. Expanding Earth and B. Contracting Earth
Halides is the term given to the ions of halogens. Halogens are the second-to-the-last column or period in the periodic table. Examples are chlorine, fluorine, bromine and iodine. Halides are all soluble in water except when combine with silver, lead and mercury. <em>Therefore, the generalization we can make is that silver halides are insoluble in water,</em>