Does anyone have science Module 2 DBA notes. Im desperate

How many moles of tin atoms are in a pure tin cup with a mass of 37.6 g ?

Georgia [21]

Tin is an element called Stannum and has the symbol Sn. Molar mass is the mass of 1 mol of a compound, 1 mol of any substance is made of 6.022 x 10²³ units, these units could be atoms making up an element or molecules making up a compound.
While the number of atoms making up 1 mol is the same for any element, the weight of 1 mol of substance varies from one another.
In tin(Sn) molar mass - 118.71 g/mol
In 118.71 g - there's 1 mol of tin
therefore in 37.6 g of tin - 1 x 37.6 / 118.71 = 0.31 mol
In 37.6 g of tin, there's 0.31 mol

3 0

3 years ago

A compound contains only change and n combustion of 35.0mg of the compound produces 33.5mg co2 and 41.1mg h2o. What is the empir

Viefleur [7K]

Answer:

The empirical formula is CH6N2

Explanation:

A compound containing only C, H, and N yields the following data. Complete combustion of 35.0 mg of the compound produced 33.5 mg of CO2 and 41.1 mg of H2O. What is the empirical formula of the compound

Step 1: Data given

Mass of the compound = 35.0 mg = 0.035 grams

Mass of CO2 = 33.5 mg = 0.0335 grams

Mass of H2O = 41.1 mg = 0.0411 grams

Molar mass CO2 = 44.01 g/mol

Molar mass H2O = 18.02 g/mol

Molar mass C = 12.01 g/mol

Molar mass O = 16.0 g/mol

Molar mass H = 1.01 g/mol

Step 2: Calculate moles CO2

Moles CO2 = 0.0335 grams / 44.01 g/mol

Moles CO2 = 7.61 *10^-4 moles

Step 3: Calculate moles C

For 1 mol CO2 we have 1 mol C

For 7.61 *10^-4 moles CO2 we have 7.61 *10^-4 moles C

Step 4: Calculate mass C

Mass C = 7.61 *10^-4 moles * 12.01 g/mol

Mass C = 0.00914 grams = 9.14 mg

Step 5: Calculate moles H2O

Moles H2O = 0.0411 grams / 18.02 g/mol

Moles H2O = 0.00228 moles

Step 6: Calculate moles H

For 1 mol H2O we have 2 moles H

For 0.00228 moles H2O we have 2* 0.00228 = 0.00456 moles H

Step 7: Calculate mass H

Mass H = 0.00456 moles * 1.01 g/mol

Mass H = 0.00461 grams = 4.61 mg

Step 8: Calculate mass N

Mass N = 35.0 mg - 9.14 - 4.61 = 21.25 mg = 0.02125 grams

Step 9: Calculate moles N

Moles N = 0.02125 grams / 14.0 g/mol

Moles N = 0.00152 moles

Step 10: Calculate the mol ratio

We divide by the smallest amount of moes

C: 0.000761 moles / 0.000761 moles= 1

H: 0.00456 moles / 0.000761 moles = 6

N: 0.00152 moles / 0.000761 moles = 2

For every C atom we have 6 H atoms and 2 N atoms

The empirical formula is CH6N2

5 0

3 years ago

What happened when bromine reacted with aluminum?

-Dominant- [34]

Answer:

The reaction begins and builds up heat. This heat causes the aluminum to melt and float on top of the liquid bromine. Wherever the two elements meet, sparks, heat, and light are given off.

Explanation:

4 0

3 years ago

The ideal gas constant, R has several different values that could be used. Which quantity causes these differences? pressure tem

Blababa [14]

Answer : The correct option is, pressure.

Explanation :

The ideal gas equation is,

$PV=nRT$

where,

P = pressure of the gas

V = volume of the gas

n = number of moles of gas

T = temperature of the gas

R = gas constant

The value of 'R' has several different values which are :

$R=0.08205L.atm/mol.K$

$R=8.3145L.kPa/mol.K$

$R=8.3145J/mol.K$

$R=1.987cal/mol.K$

$R=0.08314L.bar/mol.K$

That means, the value of 'R' is different due the change in the pressure value and all the variables (temperature, volume and moles) are constant.

Hence, the correct option is, pressure.

3 0

3 years ago

Label A is showing___ frequency waves, and label B is showing ___ frequency waves

igomit [66]

It's not really possible to tell longitudinal vs. transverse in this image as given. However, we can say that the waves labeled A are high-frequency (short wavelengths) while the waves labeled B are low-frequency (long wavelengths). So, this third answer choice would be correct here.

6 0

3 years ago