Answer:
THE MASS OF 7.68 *10^24 MOLECULES OF PHOSPHORUS TRICHLORIDE IS 1746.25 g.
Explanation:
Molar mass of PCl3 = ( 31 + 35.5 *3) = 137.5 g/mol
At 7.68 * 10^24 molecules, how many number of mole is present?
6.03 * 10^23 molecules = 1 mole
7.68*10^24 molecules = x mole
x mole = 7.68 *10^24 molecules/ 6.03 *10^23
x mole = 1.27 *10 moles
x mole = 12.7 moles
Using mole = mass / molar mass
mass = mole * molar mass
mass = 12.7 moles * 137.5 g/mol
mass = 1746.25 g
Hence, the mass of 7.68 *10^24 molecules is 1746.25 g
<h2>
Hello!</h2>
The answer is:
When the pressure that a gas exerts on a sealed container changes from
22.5 psi to 19.86 psi, the temperature changes from 110°C to
65.9°C.
<h2>
Why?</h2>
To calculate which is the last pressure, we need to use Gay-Lussac's law.
The Gay-Lussac's Law states that when the volume is kept constant, the temperature (absolute temperature) and the pressure are proportional.
The Gay-Lussac's equation states that:

We are given the following information:
We need to remember that since the temperatures are given in Celsius degrees, we need to convert it to Kelvin (absolute temperature) before use the equation, so:

Now, calculating we have:

Hence, the final pressure is equal to 19.86 Psi.
Have a nice day!
Answer:
the Bohr model, an electron's position is known precisely because it orbits the nucleus in a fixed path. In the electron cloud model, the electron's position cannot be known precisely. Only its probable location can be known.
Answer:
amino group
Explanation:
There are twenty (20) amino acids in nature. Generally, each amino acid is structurally made up of a central carbon atom called alpha carbon attached to a hydrogen, carboxylic acid group (-COOH) and an amine group (-NH2). However, one particular amino acid called PROLINE posseses an exception to this.
Proline, which is the only cyclic amino acid, is also the only amino acid that forms a secondary amine group i.e. loss of hydrogen atoms in its amine group when in a protein structure. This means that when in a protein, PROLINE does not have an AMINE GROUP.