A scoop of potassium oxide was placed in

A compound is 12.7% Al, 19.7% N, and 67.6% O. Determine its emperical formula.

gizmo_the_mogwai [7]

Answer:

AlN₃O₉

Explanation:

Assume that you have 100 g of the compound.

Then you have 12.7 g Al, 19.7 g N, and 67.6 g O.

1. Calculate the <em>moles</em> of each atom

Moles of Al = 12.7 × 1/26.98 = 0.4707 mol Al

Moles of N = 19.7 × 1/14.01 = 1.406 mol N

Moles of O = 67.6 × 1/16.00 = 4.225 mol O

2. Calculate the <em>molar ratios</em>.

Al: 0.4707/0.4707 = 1

N: 1.406/0.4707 = 2.987

O: 4.225/0.4707 = 8.976

3. Determine the <em>empirical formula</em>

Round off all numbers to the closest integer.

Al: 1

N: 3

O: 9

The empirical formula is AlN₃O₉.

3 0

4 years ago

Tris base has a molecular weight of 121 g/mol. How many grams of tris base would you need to make 250ml of a 200mM SOLUTION

STatiana [176]

Answer:

6.05 g

Explanation:

Molarity of a substance , is the number of moles present in a liter of solution .

M = n / V

M = molarity

V = volume of solution in liter ,

n = moles of solute ,

From the question ,

M = 200mM

Since,

1 mM = 10⁻³ M

M = 200 * 10⁻³ M

V = 250 mL

Since,

1 mL = 10⁻³ L

V = 250 * 10⁻³ L

The moles can be calculated , by using the above relation,

M = n / V

Putting the respective values ,

200 * 10⁻³ M = n / 250 * 10⁻³ L

n = 0.05 mol

Moles is denoted by given mass divided by the molecular mass ,

Hence ,

n = w / m

n = moles ,

w = given mass ,

m = molecular mass .

From the question ,

m = 121 g/mol

n = 0.05 mol ( calculated above )

The mass of tri base can be calculated by using the above equation ,

n = w / m

Putting the respective values ,

0.05 mol = w / 121 g/mol

w = 0.05 mol * 121 g/mol

w = 6.05 g

3 0

4 years ago

Read 2 more answers

5.60 g of an unknown gas at STP fills a 500 mL flask. What is the molar mass of the gas

ale4655 [162]

Hey there!

From ideal gas equation we know, PV = nRT

All the terms have their usual significance.

PV =w/M * RT

( where , n is number of moles = w/M, we = weight of gas, M = molecular weight of the gas)

Therefore, PV = wRT/M

At standard conditions , value of pressure, P = 1atm and standard temperature, T = 273K

And value of universal gas constant, R = 0.082 lit. atm. K⁻¹.mol⁻¹

Given that, weight of gas,

w = 5.60g and volume of gas,

V = 500mL = 0.5 Liters

Therefore, substituting all the value, we get :

Molar mass = 5.60 * 0.082 * 273 / 1 * 0.5

Molar mass = 250.7232 g/mole

3 0

4 years ago

In clinical brachytherapy, the supervision of radio elements and dose interpretation are performed by the therapeutic __________

Alex_Xolod [135]

Answer:

Radiation oncologist.

Explanation:

Cancer is one of the most deadly disease and half of the world population died due to cancer every year. Cancer might occur due to the mutation in the genes that control the cell cycle.

The oncologist may be defined as the individual that has specialized in the cancer and its treatment. The different radiation might use to kill the cancerous cell and the radio elements are administered in the drugs used during the chemotherapy.

Thus, the answer is radiation oncologist.

4 0

4 years ago

Which of the following stage is also known as the unstable stage?

Lelechka [254]

Transient stage is also called the unstable stage and in this stage, there is a gradual decrease in deformation rate to a definite constant value.

<h3>What is Transient stage ?</h3>

A transient state is when a process variable or variables changes, but before the system reaches a steady state.

Transient time is the time it takes for a circuit to change from one steady state to the next.

Therefore, Transient stage is also called the unstable stage and in this stage, there is a gradual decrease in deformation rate to a definite constant value.

Learn more about Transient stage here ;

brainly.com/question/22686897

#SPJ1

4 0

2 years ago