Answer: There are 0.000043 moles of melatonin.
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:

given mass = 10 mg = 0.01 g
molar mass of
= 232.28 g
Thus there are 0.000043 moles of melatonin
Answer:
Substance is Aluminium
Explanation:
We are given;
Mass; m = 13.5 grams
Volume; V = 5 cm³
Formula for density is;
density = m/V
Density = 13.5/5
Density = 2.7 g/cm³
From the table attached, we can see that the element with a corresponding density of 2.7 is Aluminium
Networks of feeding relationships is correct
The lowest value of the henry's law for methane gas (CH₄) will be obtained with H₂O as the solvent and a temperature of 349 K.
The lowest value of the henry's law for methane gas (CH₄) will be obtained with H₂O as the solvent and a temperature of 349 K.
Henry's law: This law states that at a constant temperature, the amount of a gas dissolved in a given type and volume of liquid is directly proportional to the partial pressure of that gas that in equilibrium with that liquid.
Mathematically it can be written as:

So, for the methane gas , lowest value of the henry's law obtained at 349 K and with H₂O as the solvent.
<u>Answer:</u> The gas produced when sodium phosphide reacts with water is phosphine.
<u>Explanation:</u>
When sodium phosphide reacts with water molecule, it leads to the production of flammable, poisonous gas known as phosphine along with the production of sodium hydroxide.
The chemical reaction for the reaction of sodium phosphide with water follows the equation:

By Stoichiometry of the reaction:
1 mole of sodium phosphide reacts with 3 moles of water to produce 1 mole of phosphine gas and 3 moles of sodium hydroxide.
Hence, the gas produced when sodium phosphide reacts with water is phosphine.