The dimensions of a rectangular solid are measured to be 1.27 cm, 1.3 cm, and 2.5 cm. The volume should be recorded as

For each pair below, select the sample that contains the largest number of moles. Pair A 2.50 g O2 2.50 g N2

raketka [301]

Answer:

Explanation:

Pair 2.50g of O₂ and 2.50g of N₂

The atoms sample with the largest number of moles since the masses are the same would be the one with lowest molar mass according the the equation below:

Number of moles = $\frac{mass }{molarmass}$

Atomic mass of O = 16g and N = 14g

Molar mass of O₂ = 16 x 2 = 32gmol⁻¹

Molar mass of N₂ = 14 x 2 = 28gmol⁻¹

Number of moles of O₂ = $\frac{2.5}{32}$ = 0.078mole

Number of moles of N₂ = $\frac{2.5}{28}$ = 0.089mole

We see that N₂ has the largest number of moles

4 0

3 years ago

Read 2 more answers

Blank c2h4 + blank o2 → blank co2 + blank h2o how many moles of o2 are in the chemical equation when balanced using the lowest w

umka21 [38]

The reaction is
C₂H₄ + O₂ → CO₂ + H₂O

To balance the equation, both side have same number of elements. Here,

In left hand side has in right hand side has

4 H atoms 2 H atoms

2 C atoms 1 C atom

2 O atoms 3 O atoms

First, we have to balance number of C atoms and number of H atoms in both side.
To balance C atoms, '2' should be added before CO₂ and to balance H atoms, '2' should be added before H₂O.
Then number of oxygen atoms is 2 x 2 + 2 = 6 in right hand side. So, 3 should be added before O₂ in left hand side.
After balancing the equation should be,

C₂H₄ + 3O₂ → 2CO₂ + 2H₂O

8 0

3 years ago

An electron has an uncertainty in its position of 513 pm. What is the uncertainty in its velocity?

ella [17]

"The uncertainty in velocity is Δv=1.05⋅105m/s . According to the Heisenberg Uncertainty Principle, you cannot measure simultaneously with great precision both the momentum and the position of a particle. m - the mass of an electron - 9.10938⋅10−31kg."
-socratic.com

7 0

3 years ago

Question 3) A 1.00 L buffer solution is 0.250 M in HF and 0.250 M in LiF. Calculate the pH of the solution after the addition of

Masja [62]

The pH of the solution after adding 0.150 moles of solid LiF is 3.84

Explanation:

We have the chemical equation,

HF (aq)+NaOH(aq)->NaF(aq)+H2O

To find how many moles have been used in this

c= n/V=> n= c.V

nHF=0.250 M⋅1.5 L=0.375 moles HF

Simillarly

nF=0.250 M⋅1.5 L=0.375 moles F

nHF=0.375 moles - 0.250 moles=0.125 moles

nF=0.375 moles+0.250 moles=0.625 moles

[HF]=0.125 moles/1.5 L=0.0834 M

[F−]=0.625 moles/1.5 L=0.4167 M

To determine the problem using the Henderson - Hasselbalch equation

pH=pKa+log ([conjugate base/[weak acid])

Find the value of Ka

pKa=−log(Ka)

pH=−log(Ka) +log([F−]/[HF]

pH= -log(3.5 x 10 ^4)+log(0.4167 M/0.0834 M)

pH=-log(3.5 x 10 ^4)+log(4.996)

pH= -4.54+0.698

pH=-(-3.84)

pH=3.84

The pH of the solution after adding 0.150 moles of solid LiF is 3.84

5 0

4 years ago

The volume of air in a person’s lungs is 615 mL at a pressure of 760. mmHg. Inhalation occurs as the pressure in the lungs drops

chubhunter [2.5K]

Answer: The final volume of lungs is 621.5 mL

Explanation:

To calculate the new volume, we use the equation given by Boyle's law. This law states that pressure is inversely proportional to the volume of the gas at constant temperature.

The equation given by this law is:

$P_1V_1=P_2V_2$