HELP ASAP WILL AWARD 60 Points

you need 16.66ml (+-0.01) of 53.4 (+-0.4)wt% of NaOH with a density of 1.52 (+-0.01)g/mL to prepare 2.00L of 0.169M of NaOH. Wha

pashok25 [27]

Answer:

The absolute uncertainty is approximately 1.69 × 10⁻³

Explanation:

The volume needed for NaOH needed to make the solution = 16.66 ml

The wt% of the added NaOH = 53.4 wt%

The volume of the NaOH to be prepared = 2.00 L

The concentration of the NaOH to be prepared = 0.169 M

The molar mass of NaOH = 39.997 g/mol

Therefore, 100 g of sample contains 53.4 g of NaOH

The mass of the sample = 16.66 × 1.52 = 25.3232 g

The mass of NaOH in the sample = 0.534 × 25.3232 = 13.5225888 g ≈ 13.52 g

Therefore;

The number of moles of NaOH = 13.52/39.9971 = 0.3381 moles

Therefore, we have 0.3381 moles in 2.00L solution, which gives;

The number of moles per liter = 0.3881/2 = 0.169045 moles/liter

The molarity ≈ 0.169 M

The absolute uncertainty, u(c) is given as follows;

$u(c) = \sqrt{ \left (\dfrac{0.01}{16.66} \right )^2 + \left ( \dfrac{0.4}{53.4} \right )^2 + \left ( \dfrac{0.01}{1.52} \right )^2 } \times 0.169 \approx 1.69 \times 10^{-3}$

The absolute uncertainty, u(c) ≈ 1.69 × 10⁻³.

3 0

3 years ago

What are the reasons that require a person to engage in philosophical thinking?

BartSMP [9]

The word "philosophy" comes from Greek roots meaning "love of wisdom." In fact, broadly stated, philosophy is the pursuit of wisdom or knowledge using your innate ability to think rationally and systematically. When you engage in philosophical thinking, you are using assumptions to better understand yourself and.

8 0

3 years ago

Which statement is true about BF3, a nonpolar molecule? It has nonpolar bonds and a symmetrical structure. It has nonpolar bonds

konstantin123 [22]

I think the correct answer is the first option. It has nonpolar bonds and a symmetrical structure. The structure of a BF3 molecule shows a symmetrical trigonal geometry. The net dipole moment of the molecule is zero therefore it is polar.

6 0

3 years ago

Read 2 more answers

A mixture of carbon dioxide and helium gases is maintained in a 7.91 L flask at a pressure of 1.42 atm and a temperature of 33 °

Crank

Answer:

The gas mixture contains 1.038 grams of helium

Explanation:

Step 1: Data given

Volume of the flask = 7.91 L

Total Pressure = 1.42 atm

Temperature = 33 °C

Mass of CO2 = 8.25 grams

Molar mass of CO2 = 44.01 g/mol

Molar mass of He = 4 g/mol

Step 2: Calculate total number moles of gas

p*V = n*R*T

⇒ p = the pressure = 1.42 atm

⇒ V = the volume = 7.91 L

⇒ n= the number of moles = TO BE DETERMINED

⇒ R = the gas constant = 0.08206 L* atm/K*mol

⇒ T = the temperature = 33 °C = 306 Kelvin

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

n = (1.42*7.91)/(0.08206 * 306)

n = 0.447 moles

Step 3: Calculate moles of CO2

Moles CO2 = mass CO2 / Molar mass CO2

Moles CO2 = 8.25 grams / 44.01 g/mol

Moles CO2 = 0.1875 moles

Step 4: Calculate moles of Helium

Moles Helium = total moles of gas - moles of CO2

Moles Helium = 0.447 - 0.1875 = 0.2595 moles of helium

Step 5: Calculate mass of helium

Mass of helium = moles of helium * molar mass of helium

Mass of helium = 0.2595 moles * 4 g/mol

Mass of helium = 1.038 grams

The gas mixture contains 1.038 grams of helium

8 0

3 years ago

What causes an earthquake?

nirvana33 [79]

Answer:The earths plates shifting

Explanation: The movement releases stored-up 'elastic strain' energy in the form of seismic waves, which propagate through the Earth and cause the ground surface to shake.

6 0

3 years ago