Which one of these is it?

Consider this reaction involving an unknown element X. F2+2XBr⟶Br2+2XF When 1.300 g of XBr reacts, 0.7241 g of Br2 is produced.

scZoUnD [109]

The molar mass of X would be 63.55 g/mol and the chemical symbol of X would be Cu (copper).

From the equation of the reaction: F2+2XBr⟶Br2+2XF

The mole ratio of XBr to Br2 is 2:1

Mole of Br2 = mass/molar mass

= 0.7241/159.808

= 0.004531 mole

Mole of XBr = 2 x mole of Br2

= 2 x 0.004531

= 0.009062 mole

Molar mass of XBr = mass/mole

= 1.300/0.009062

= 143.456 g/mol

Since the molar mass of Br is 79.904, the molar of X would be:

143.456 - 79.904

= 63.55 g/mol

Hence, X would be Cu.

More on molar mass calculation can be found here: brainly.com/question/20691135

6 0

2 years ago

What is the molar mass of CHCl3?<br> 48.47 g/mol<br> 83.92 g/mol<br> 119.37 g/mol<br> 121.39 g/mol

kolbaska11 [484]

119.37 g/mol

<h3>Further explanation</h3>

Relative atomic mass (Ar) and relative molecular mass / molar mass (M)

the molar mass/molecular mass of a compound : the sum of the relative atomic mass (Ar) of the constituent atoms

M AxBy = (x.Ar A + y. Ar B)

Atomic weight (Ar) of :

C : 12.0107 g/mol
H : 1.00784 g/mol
Cl : 35.453 g/mol

The molar mass of CHCl₃

$\tt CHCl_3=12.0107+1,00784+(35,453\times 3)=119.37~g/mol$

8 0

2 years ago

Read 2 more answers

Use bond energies to calculate ΔHrxn Δ H r x n for the reaction. 2H2(g)+O2(g)→2H2O(g) 2 H 2 ( g ) + O 2 ( g ) → 2 H 2 O ( g )

Olenka [21]

Answer:

$\large \boxed{\text{-486 kJ}}$

Explanation:

You calculate the energy required to break all the bonds in the reactants.

Then you subtract the energy needed to break all the bonds in the products.

2H₂ + O₂ ⟶ 2H-O-H

Bonds: 2H-H 1O=O 4H-O

D/kJ·mol⁻¹: 436 498 464

$\begin{array}{rcl}\Delta H & = & \sum{mD_{\text{reactants}}} - \sum{nD_{\text{products}}}\\& = & 2 \times 436 +1 \times 498 - 4 \times 464\\&=& 1370 - 1856\\&=&\textbf{-486 kJ}\\\end{array}\\\text{The enthalpy of reaction is $\large \boxed{\textbf{-486 kJ}}$}.$

3 0

2 years ago

Can someone pleas help

bekas [8.4K]

Answer:

Looks like a balloon to me

Explanation:

3 0

3 years ago

We can also use the equation for enthalpy change for physical phase changes. Consider the phase change H2O(l) → H2O(g). Calculat

VLD [36.1K]

Answer: The value of enthalpy of the given reaction is 44.000 kJ/mol , that is energy is supplied to water to change into water vapors

Explanation:

$H_2O(l)\rightarrow H_2O(g),\Delta H_{rxn}=?$

Enthalpy of formation of water in liquid state, $\Delta H_{f,H_2O(l)}=-285.820 kJ/mol$

Enthalpy of formation of water in gaseous state, $\Delta H_{f,H_2O(g)}=-241.820 kJ/mol$

$\Delta H_{rxn}=\sum \Delta H_f \text{of products}-\sum \Delta H_f \text{of reactants}$

$\Delta H_{rxn}=(-241.820 kJ/mol)-(-285.820 kJ/mol)=44.000 kJ/mol$

The value of enthalpy of the given reaction is 44.000 kJ/mol, that is energy is supplied to water to change into water vapors.

6 0

3 years ago

Read 2 more answers