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1 year ago

Why is the average atomic mass in the periodic table a decimal?

1 answer:

4 0

Many of the atomic masses listed on the periodic table are decimal values because it's the weighted average mass of all of the isotopes of that element.

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Determine the theoretical yield of P2O5, when 3.07 g of P reacts with 6.09 g of oxygen in the following chemical equation

saveliy_v [14]

Answer: 14.2 grams

Explanation:-

According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number $6.023\times 10^{23}$ of particles.

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

given mass of phosphorous (P) = 3.07 g

Molar mass of phosphorous (P) = 31 g/mol

Putting in the values we get:

$\text{Number of moles of phosphorous}=\frac{3.07g}{31g/mol}=0.1moles$

given mass of oxygen $O_2$ = 6.09 g

Molar mass of oxygen $O_2$ = 32 g/mol

Putting in the values we get:

$\text{Number of moles of oxygen}=\frac{6.09g}{32g/mol}=0.2moles$

According to stoichiometry:

$4P+5O_2\rightarrow 2P_2O_5$

4 moles of phosphorous combine with 5 moles of oxygen

Thus 0.1 moles of phosphorous combine with = $\frac{5}{4}\times 0.1=0.125$ moles of oxygen

Thus phosphorous acts as limiting reagent as it limits the formation of product and oxygen is the excess reagent.

4 moles of phosphorous gives= 2 moles of $P_2O_5$

Thus 0.1 moles of phosphorous gives = $\frac{2}{4}\times 0.1=0.05$ moles of $P_2O_5$

mass of $P_2O_5=moles\times {\text {Molar mass}}=0.05\times 284=14.2g$

Thus the theoretical yield of $P_2O_5$ is 14.2 grams.

5 0

3 years ago

Type the letter that represents the correct location for each particle type below.

DerKrebs [107]

The electrons are found in shells or orbits that surround the nucleus of an atom

Protons and neutrons are found in the nucleus . They group in the center of the atom

4 0

3 years ago

Read 2 more answers

What is the molality of a solution made by dissolving 2 moles of NaOH in 10 kg of water?

zaharov [31]

Answer:

0.2mol/kg

Explanation:

molality is the concentration of a solution in moles of solute per kilogram of solvent

moles of solute (NaOH) = 2moles

mass of solvent in kg. =10kg

Therefore molality. = 2moles/10 kg