Sxty-D<br><br> 1. What fraction of the elements on the periodic table are metals?

Based on the equation, how many grams of Br2 are required to react completely with 36.2 grams of AlCl3?

s2008m [1.1K]

Answer:

65.08 g.

Explanation:

For the reaction, the balanced equation is:

2.0 mole of AlCl₃ reacts with 3.0 mole of Br₂ to produce 2.0 mole of AlBr₃ and 3.0 mole of Cl₂.

Firstly, we need to calculate the no. of moles of 36.2 grams of AlCl₃:

<em>n = mass/molar mass</em> = (36.2 g)/(133.34 g/mol) = <em>0.2715 mol.</em>

<u><em>Using cross multiplication:</em></u>

2.0 mole of AlCl₃ reacts with → 3.0 mole of Br₂, from the stichiometry.

0.2715 mol of AlCl₃ reacts with → ??? mole of Br₂.

∴ The no. of moles of Br₂ reacts completely with 0.2715 mol (36.2 g) of AlCl₃ = (0.2715 mol)(3.0 mole)/(2.0 mole) = 0.4072 mol.

<em>∴ The mass of Br₂ reacts completely with 0.2715 mol (36.2 g) of AlCl₃ = no. of moles of Br₂ x molar mass</em> = (0.4072 mol)(159.808 g/mol ) = <em>65.08 g.</em>

4 0

3 years ago

How many liters of hydrogen gas will be produced at STP from the reaction of 7.179 x 1023 atoms of magnesium with 54.21 g of pho

wlad13 [49]

<h3>Answer:</h3>

18.58 liters of hydrogen gas

<h3>Explanation:</h3>

We are given;

The equation;

3Mg + 2H₃(PO₄) → Mg₃(PO₄)₂ + 3H₂

Atoms of Magnesium = 7.179 x 10^23 atoms
Mass of phosphoric acid as 54.21 g

We are required to determine the volume of hydrogen gas produced;

Step 1; moles of Magnesium

1 mole of an element contains 6.02 × 10^23 atoms

therefore;

Moles of Mg = (7.179 x 10^23 ) ÷ (6.02 × 10^23)

= 1.193 moles

Step 2: Moles of phosphoric acid

moles = Mass ÷ Molar mass

Molar mass of phosphoric acid = 97.994 g/mol

Therefore;

Moles of Phosphoric acid = 54.21 g ÷ 97.994 g/mol

= 0.553 moles

Step 3: Determine the rate limiting reagent

From the mole ratio of Mg to Phosphoric acid (3 : 2);

1.193 moles of magnesium requires 0.795 moles of phosphoric acid while,

0.0553 moles of phosphoric acid requires 0.8295 moles of Mg

Therefore, phosphoric acid is the rate limiting reagent

step 4: Determine the moles of hydrogen produced

From the equation, w moles of phosphoric acid reacts to produce 3 moles of hydrogen;

Therefore; moles of Hydrogen = moles of phosphoric acid × 3/2

= 0.553 moles × 3/2

= 0.8295 moles

Step 5: Volume of hydrogen gas

1 mole of a gas occupies a volume of 22.4 liters at STP

Therefore;

Volume of Hydrogen = 0.8295 moles × 22.4 L/mol

= 18.58 Liters

Therefore; 18.58 liters of hydrogen gas will be produced

4 0

3 years ago

Ca(s) + O₂(g) + S(s) → CaSO4(s)

san4es73 [151]

The mass of Calcium required to complete this reaction is 4.008 g.

Law of conservation of mass states that In a closed system, mass cannot be produced or destroyed, but it can be changed from one form to another.
The mass of the chemical constituents before a chemical reaction is equal to the mass of the constituents after the reaction.
In several disciplines, including chemistry, mechanics, and fluid dynamics, the idea of mass conservation is widely applied.

In the given reaction mass of product after completion of reaction is 13.614 g that means total mass of constituents before reaction should also be 13.614.

So,

mass of Ca + mass of O₂ + mass of S = mass of CaSO4

Ca + 6.400 g + 3.206 g = 13.614 g

mass of Ca = 13.614 - 9.606 = 4.008 g

Therefore, by law of conservation of mass 4.008 g of Ca is required for the completion of the reaction.

Learn more about mass conservation here:

brainly.com/question/2030891

#SPJ9

5 0

1 year ago

A 0.1 gram sample of an unknown liquid is vaporized completely at 70 degrees C to fill a 750mL flask. The pressure is 0.05951atm

Deffense [45]

Answer:

The molar mass of the liquid 62.89 g/mol

Explanation:

Step 1: Data given

Mass of the sample = 0.1 grams

Temperature = 70°C

Volume = 750 mL

Pressure = 0.05951 atm

Step 2: Calculate the number of moles

p*V = n*R*T

n = (p*V)/(R*T)

⇒ with n = the number of moles gas = TO BE DETERMINED

⇒ with p = The pressure = 0.05951 atm

⇒ with V = The volume of the flask = 750 mL = 0.750 L

⇒ with R = The gasconstant = 0.08206 L*atm/K*mol

⇒with T = the temperature = 70 °C = 343 Kelvin

n = (0.05951 *0.750)/(0.08206*343)

n = 0.00159 moles

Step 3: Calculate molar mass

Molar mass = mass / moles

Molar mass =0.1 gram / 0.00159 moles

Molar mass = 62.89 g/mol

The molar mass of the liquid 62.89 g/mol

6 0

3 years ago

What mass of cu(s) is electroplated by running 26.5 a of current through a cu2+(aq) solution for 4.00 h?

kramer

T = 14400 s
26.5 x 14400=381600 C
381600/96500=3.95 Faradays
Cu2+ + 2e- = Cu
3.95 faradays ( 1 mol/ 2 Faradays) = 1.97
mass = 1.97 x 63.55 g/mol=125 g

moles Au = 33.1 / 196.967 g/mol=0.168
Au+ + 1e- = Au
0.168 ( 1 Faraday/ 1mol)= 0.168 Faraday
0.168 x 96500=16217 Coulombs
16217 / 5.00=3243 s => 54 min

7 0

3 years ago

Sxty-D 1. What fraction of the elements on the periodic table are metals?