Which of the following elements is a metalloid? A. vanadium (V) B. radon (Rn) C. silicon (Si) D. rubidium (Rb)

Given the reaction to 2NaOH + H2 SO4 â Na2 SO4 + 2H2 O, what is the total number of grams of NaOH needed to react completely wit

vfiekz [6]

Answer:

4 moles, 160 g

Explanation:

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

For $H_2SO_4$ :-

Mass of $H_2SO_4$ = 196 g

Molar mass of $H_2SO_4$ = 98 g/mol

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus,

$Moles= \frac{196\ g}{98\ g/mol}$

$Moles\ of\ Sulfuric\ acid= 2\ mol$

According to the given reaction:

$2NaOH+H_2SO_4\rightarrow Na_2SO_4+2H_2O$

1 mole of sulfuric acid reacts with 2 moles of NaOH

So,

2 moles of sulfuric acid reacts with 2*2 moles of NaOH

Moles of NaOH must react = 4 moles

Molar mass of NaOH = 40 g/mol

<u>Mass = Moles*molar mass = $4\times 40\ g$ = 160 g</u>

7 0

3 years ago

Consider the reaction Mg₂Si(s) + 4 H₂O(ℓ) → 2 Mg(OH)₂(aq) + SiH₄(g). How many grams of silane gas (SiH₄) are formed if 25.0 g of

Neko [114]

Answer:

10.60 grams of silane gas are formed.

Explanation:

From the reaction:

Mg₂Si(s) + 4H₂O(l) → 2Mg(OH)₂(aq) + SiH₄(g)

We know that the limiting reactant is Mg₂Si, so to find the mass of SiH₄ formed we need to calculate the number of moles of Mg₂Si:

$\eta_{Mg_{2}Si} = \frac{m_{Mg_{2}Si}}{M_{Mg_{2}Si}}$

Where:

m: is the mass of Mg₂Si = 25.0 g

M: is the molar mass of Mg₂Si = 76.69 g/mol

$\eta_{Mg_{2}Si} = \frac{m_{Mg_{2}Si}}{M_{Mg_{2}Si}} = \frac{25.0 g}{76.69 g/mol} = 0.33 moles$

Now, the stoichiometric relation between Mg₂Si and SiH₄ is 1:1 so:

$\eta_{Mg_{2}Si} = \eta_{SiH_{4}} = 0.33 moles$

Finally, the mass of SiH₄ is:

$m_{SiH_{4}} = \eta_{SiH_{4}}*M_{SiH_{4}} = 0.33 moles*32.12 g/mol = 10.60 g$

Therefore, 10.60 grams of silane gas are formed.

I hope it helps you!

3 0

3 years ago

O POMICU

Alexus [3.1K]

Answer:

Your correct one is the 3rd one!

6 0

3 years ago

Read 2 more answers

Why must the chemical equation be balanced ?

elena-14-01-66 [18.8K]

Answer:

D

Explanation:

the answer is d as the law of conservation must be hold good during the equation

3 0

4 years ago

When naming organic compounds, there are strict rules regarding punctuation.

docker41 [41]

The question is incomplete, the complete question is shown in the image attached to this answer

Answer:

2,3,3-trimethylhexane

Explanation:

IUPAC nomenclature provides a universally acceptable method of naming organic compounds from its structure.

According to this system of nomenclature;

A comma is used to separate two numbers.

A hyphen is used to separate a number from a letter.

Applying these rules, the name of the compound shown in the question should be written as 2,3,3-trimethylhexane.

8 0

4 years ago