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2 years ago

¿Qué son los lantánidos y actínidos?

1 answer:

6 0

Answer: En estos grupos de los elementos de transición se encuentran las llamadas tierras raras, separadas del resto de elementos de la tabla, que pertenecen al grupo IIIB y se les conoce como lantánidos y actínidos.

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The main-group elements are the forty-four elements that occupy groups 1A-8A of the periodic table. Main-group elements are impo

nignag [31]

Answer:

The answer is a,b, and c. This is for the USA tesprep videos

Explanation:

7 0

2 years ago

A 6.00 L vessel contains 20.0 g of PCl3 and 3.15 g of O2 at 15.0 ∘C. The vessel is heated to 210 ∘C, and the contents react to g

dusya [7]

Answer: The final pressure in the vessel will be 0.965 atm

Explanation:

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

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ .....(1)

For phosphorus trichloride:

Given mass of phosphorus trichloride = 20.0 g

Molar mass of phosphorus trichloride = 137.3 g/mol

Putting values in equation 1, we get:

$\text{Moles of phosphorus trichloride}=\frac{20.0g}{137.3g/mol}=0.146mol$

For oxygen gas:

Given mass of oxygen gas = 3.15 g

Molar mass of oxygen gas = 32 g/mol

Putting values in equation 1, we get:

$\text{Moles of oxygen gas}=\frac{3.15g}{32g/mol}=0.098mol$

The chemical equation for the reaction of phosphorus trichloride and oxygen gas follows:

$2PCl_3+O_2\rightarrow 2POCl_3$

By Stoichiometry of the reaction:

2 moles of phosphorus trichloride reacts with 1 mole of oxygen gas

So, 0.146 moles of phosphorus trichloride will react with = $\frac{1}{2}\times 0.146=0.073mol$ of oxygen gas

As, given amount of oxygen gas is more than the required amount. So, it is considered as an excess reagent.

Thus, phosphorus trichloride is considered as a limiting reagent because it limits the formation of product.

By Stoichiometry of the reaction:

2 moles of phosphorus trichloride produces 2 moles of $POCl_3$

So, 0.146 moles of phosphorus trichloride will produce = $\frac{2}{2}\times 0.146=0.146mol$ of $POCl_3$

To calculate the pressure of the vessel, we use the equation given by ideal gas follows:

$PV=nRT$

where,

P = pressure of the vessel = ?

V = Volume of the vessel = 6.00 L

T = Temperature of the vessel = $210^oC=[210+273]K=483K$

R = Gas constant = $0.0821\text{ L. atm }mol^{-1}K^{-1}$

n = number of moles = 0.146 moles

Putting values in above equation, we get:

$P\times 6.00L=0.146mol\times 0.0821\text{ L atm }mol^{-1}K^{-1}\times 483K\\\\P=\frac{0.146\times 0.0821\times 483}{6.00}=0.965atm$

Hence, the final pressure in the vessel will be 0.965 atm

3 0

3 years ago

Read 2 more answers

Which of these chemical formulas represents both an element and a molecule?

inna [77]

O2.

Because it is only made up of one type of element it is an element. Howevern there is more than one oxygen atom because oxygen cannot exist as a single atom, therefore making it a molecule as well.

8 0

3 years ago

Read 2 more answers

How many milliliters of an aqueous solution of 0.193 M potassium carbonate is needed to

VikaD [51]

Answer:

295 mL

Explanation:

Given data:

Volume needed = ?

Molarity of solution = 0.193 M

Mass of salt = 7.90 g

Solution:

Molarity = number of moles of solute / volume in L

Number of moles of salt = mass/molar mass

Number of moles of salt = 7.90 g/ 138.205 g/mol

Number of moles = 0.057 mol

Volume needed:

Molarity = number of moles / volume in L

0.193 M = 0.057 mol / volume in L

Volume in L = 0.057 mol / 0.193 M

Volume in L = 0.295 L

L into mL

0.295 L × 1000 mL/1L

295 mL

6 0

3 years ago

Atoms of one element are converted to atoms of another element through

lubasha [3.4K]

Atoms of one element are converted to atoms of another element through transmutation or nuclear transmutation.

6 0

3 years ago