Hurry

Which statement best illustrates vibrational motion?

jekas [21]

C. Cello playing music at a concert

8 0

3 years ago

Read 2 more answers

What is 0.00034 in exponential form

Verizon [17]

Answer:

3.4 × 10 ^− 4

Explanation:

Move the decimal so there is one non-zero digit to the left of the decimal point. The number of decimal places you move will be the exponent on the

10 . If the decimal is being moved to the right, the exponent will be negative. If the decimal is being moved to the left, the exponent will be positive.

7 0

3 years ago

For the solution resulting from dissolved 0.32 g of naphthalene (C10H8) in 25 g of benzene (C6H6) at temperature of 26.1°C, calc

grandymaker [24]

Answer:

See explanation

Explanation:

Number of moles of naphthalene = 0.32g/128.1705 g/mol = 0.0025 moles

Molality = number of moles/ mass of Solvent in kilograms

Molality = 0.0025/0.025 Kg

Morality = 0.1 m

But

∆T= K × i × m

Where ∆T = boiling point elevation

i= number of particles (this is equal to 1 because naphthalene is molecular and not ionic)

m= molality of naphthalene = 0.1 m

K= boiling point elevation constant = 5.12 °C/m

∆T= 5.12 °C/m ×0.1 = 0.512°C

For freezing point depression

∆T= K× i × m

Where ∆T= freezing point depression

i= number of particles (this is equal to 1 because naphthalene is molecular and not ionic)

m= molality of naphthalene = 0.1 m

K= freezing point depression constant = 2.67 °C/m

∆T= 2.67 °C/m ×0.1 = 0.267°C

From Raoult's law;

∆P = XBPA°

Where;

∆P = vapour pressure lowering

XB = mole fraction of solute

PA° = vapour pressure of pure solvent

Number of moles of solvent = mass/molar mass = 25g/ 78 g/mol= 0.3205 moles

Total number of moles = number of moles of solute + number of moles of solvent = 0.0025 moles + 0.3205 moles = 0.323 moles

Mole fraction of solute = 0.0025 moles/0.323 moles = 0.0077

Vapour pressure of benzene = 100 torr

Therefore;

∆P = 0.0077 × 100torr = 0.77 torr

Hence;

∆P = 0.77 torr

5 0

3 years ago

What are accounts for physical properties?

Nezavi [6.7K]

Freezing point, boiling point, melting point, smell, attraction or repulsion to magnets, colour change, and many more examples.

3 0

3 years ago

Suppose you have 81.8 g of Cd. How many Cd atoms are present? Report your answer in scientific notation using the format of 6.02

Lostsunrise [7]

Answer:

1. number of Cd atoms = 4.384 × 10²³

2. number of moles of Ti = 0.817 mol

3. molar mass of C₇H₆O₃ = 138.077 g/mol

4. moles of Sildenafil = 0.249 mmol

Explanation:

1. given data

mass of Cd = 81.8 g

number of Cd atoms = ?

molar mass of Cd = 112.411 g/mol

Solution

1st we find out the number of moles of Cd

number of moles = mass / molar mass

number of moles of Cd = 81.8 g / 112.411 g.mol⁻

number of moles of Cd = 0.728 mol

Now we find out the number of Cd atoms

number of atoms = moles × 6.022 × 10²³

number of Cd atoms = 0.728 (6.022 × 10²³)

number of Cd atoms = 4.384 × 10²³

2. Given data

Mass of Ti = 39.1 g

moles = ?

molar mass Ti = 47.867 g/mol

Solution

Now we will find out the number of moles

number of moles = mass / molar mass

number of moles of Ti = 39.1 g / 47.867 g.mol⁻

number of moles of Ti = 0.817 mol

3. Given data

chemical formula of Salicylic acid = C₇H₆O₃

molar mass of salicylic acid = ?

molar mass of carbon = 12.011

molar mass of hydrogen = 1.008

molar mass of oxygen = 15.999

molar mass of molecule = number of moles of atoms × molar mass of atoms

molar mass of C₇H₆O₃ = 7 (12.011) + 6 (1) + 3 (16)

molar mass of C₇H₆O₃ = 84.077 g + 6 g + 48 g

molar mass of C₇H₆O₃ = 138.077 g/mol

4. Given data

molar mass of Sildenafil = 474.5828 g/mol

mass given = 0.118 g

moles of Sildenafil = ?

Solution

Now we find out the number of moles

number of moles = mass / molar mass

number of moles Sildenafil = 0.118 g / 474.5828 g/mol

number of moles Sildenafil = 0.0003 mol

as this is very small amount we convert it into millimoles

millimoles = moles × 1000

millimoles of Sildenafil = 0.000249 × 1000

millimoles of Sildenafil = 0.249 mmol

4 0

3 years ago