All categories

3 years ago

The ion with 3+ charge 28 electons and a mass number of 71

1 answer:

6 0

The answer is ⁷¹Ga³⁺.

Substitute 28 for number of electrons, 71 for mass number, and 3 for charge on the ion. The element is Gallium and its symbol is Ga.

You might be interested in

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

The value of Kc for the reaction between water vapor and dichlorine monoxide, H2O(g) 1 Cl2O(g) 4 2 HOCl(g) is 0.0900 at 25°C. De

max2010maxim [7]

Answer:

[HOCl] = 0.001 127 mol·L⁻¹; [H₂O] = [Cl₂O] = 0.003 76 mol·L⁻¹

Explanation:

The balanced equation is

H₂O + Cl₂O ⇌ 2HOCl

Data:

Kc = 0.0900

[H₂O] = 0.004 32 mol·L⁻¹

[Cl₂O] = 0.004 32 mol

1. Set up an ICE table.

$\begin{array}{ccccccc}\rm \text{H$_{2}$O}& + & \text{Cl$_{2}$O} & \, \rightleftharpoons \, & \text{2HOCl} & & \\0.00432 & & 0.00432 & & 0 & & \\-x &&-x&&+2x&&\\0.00432-x &&0.00432 - x& & 2x&&\\\end{array}$

2. Calculate the equilibrium concentrations

$K_{\text{c}} = \dfrac{\text{[HOCl]$^{2}$}}{\text{[H$_{2}$O][Cl$_2$O]}} = \dfrac{(2x)^{2}}{(0.00432 - x)^{2}} = 0.0900\\\\\begin{array}{rcl}\dfrac{4x^{2}}{(0.00432 - x)^{2}} &=& 0.0900\\ \dfrac{2x }{0.00432 - x} & = & 0.300\\2x & = & 0.300(0.00432 - x)\\2x & = & 0.001296 - 0.300x\\2.300x & = & 0.001296\\x & = & \mathbf{5.63\times 10^{-4}}\\\end{array}$

[HOCl] = 2x mol·L⁻¹ = 2 × 5.63 × 10⁻⁴ mol·L⁻¹ =0.001 127 mol·L⁻¹

[H₂O] = [Cl₂O] = (0.004 32 - 0.000 563) mol·L⁻¹ = 0.003 76 mol·L⁻¹

Check:

$\begin{array}{rcl}\dfrac{0.001127^{2}}{0.00376^{2}} & = & 0.0900\\\\\dfrac{1.270 \times 10^{-6}}{1.411 \times 10^{-5}} & = & 0.0900\\0.0900 & = & 0.0900\\\end{array}$

OK.

7 0

3 years ago

What was the name for the spectrum of specific wavelengths produced by an existing element?

Annette [7]

The emission spectrum of a chemical element

5 0

3 years ago

Read 2 more answers

GIVING BRAINLY !!!!!! Calculate the molar mass of MgBr2. “SHOW” Your work!

Dovator [93]

Answer:

184.113 g/mol

Explanation: The atomic mass of Mg is 24.3 amu. The atomic mass of bromine is 79.9. Therefore, the formula weight of MgBr2 equals 24.3 amu + (2 × 79.9 amu), or 184.1 amu. Because a substance's molar mass has the same numerical value as its formula weight, the molar mass of MgBr2 equals 184.1 g/mol.

8 0

3 years ago

A sample is found to contain 57.2 % N a H C O 3 NaHCOX3 by mass. What is the mass of NaHCO 3 in 4.25 g of the sample

liq [111]

Answer:

The mass of N a H C O 3 present is 2.431 g

Explanation:

The sample contains 57.2 % N a H C O 3 by mass.

To find the mass of N a H C O 3 in the sample, we need to find what the equivalent of 57.2 %.

Mass of N a H C O 3 = Percentage Composition * Mass of sample

Mass of N a H C O 3 = 57.2 / 100 * 4.25

Mass of N a H C O 3 = 2.431 g

The mass of N a H C O 3 present is 2.431 g

3 0

4 years ago