How many grams are there in 7.3 moles of NH3?

What Kelvin temperature is the same as -13° Celsius?

zavuch27 [327]

Answer:

Degrees Kelvin = Degrees Celsius + 273.15

Degrees Kelvin = -13 + 273.15

= 260.15 °

Explanation:

8 0

3 years ago

During an experiment, ice and water were placed in a perfectly insulated thermos flask at 0 °C. Describe this system when it pha

Ivanshal [37]

Answer :By the time thermal equilibrium is attained in the system, ice is completely converted to water.

What is tehrmal equilibrium?

Thermal equilibrium is a situation in which two substances are exactly at the same temperature. That is. Heat is no longer flowing beween the bodies.

Recall that an insulated thermos flask implies that heat does not eneter or leave the system. Heat will flow from the water to the ice untill the both attains the same temperature and the ice is completely converted to water.

Have a good day

5 0

1 year ago

Convert 15.2 moles of K to atoms of K.

choli [55]

Answer:

$\boxed {\boxed {\sf 9.15*10^{24} \ atoms \ K}}$

Explanation:

To convert atoms to moles, Avogadro's Number must be used: 6.022*10²³.

This tells us the amount of particles (atoms, molecules, etc.) in 1 mole of a substance. In this case it is the atoms of potassium. We can create a ratio.

$\frac {6.022*10^{23} \ atoms \ K }{ 1 \ mol \ K }$

Multiply by the given number of moles: 15.2

$15.2 \ mol \ K *\frac {6.022*10^{23} \ atoms \ K }{ 1 \ mol \ K }$

The moles of potassium cancel.

$15.2 *\frac {6.022*10^{23} \ atoms \ K }{ 1 }$

The denominator of 1 can be ignored.

$15.2 * {6.022*10^{23} \ atoms \ K }{$

Multiply.

$9.15344*10^{24} \ atoms \ K$

The original measurement of moles has 3 significant figures, so our answer must have the same. For the number we calculated that is the hundredth place. The 3 in the thousandth place tells us to leave 5.

$9.15*10^{24} \ atoms \ K$

In 15.2 moles of potassium, there are <u>9.15*10²⁴ atoms of potassium.</u>

3 0

2 years ago

Which of the following is not true? a. The freezing point of sea water is lower than the freezing point of pure water. b. The bo

Anna007 [38]

Answer:

The false statement is b.

The boiling point of a water sample from the Salt Lake is lower than the boiling point of pure water

Explanation:

This excersise refers to colligative properties.

Boiling point refers to the property of boiling point elevation. In a solution of ions, as water sea or water from lakes, the boiling point will be higher than water pure.

It is logical to say that, because these sort of water have ions. Remember that colligative properties depends on the solute particles.

T° boiling solution - T° pure solvent = Kb . m . i

In the freezing point depression, we have the oppossite of boiling point elevation. Freezing point of solution is lower than pure solvent, according to this:

T° freezing pure solvent - T° freezing solution = Kc . m . i

We have to always consider the i, which means Van't Hoff factor, number of ions dissolved in solution. As the i is higher, the freezing point of solution will be lower, and the boiling point of solution will be higher.

They are true statement a and c.

In solution of., [NaCl] = 0.1M, as it is a higher concentration, the molality is also higher than a solution of [NaCl] = 0.05.

As water sample form Salt Lake has certain ions, it is logical to say that the boiling point of this water is higher than boiling point of pure water.

5 0

3 years ago

The Gateway Arch in St. Louis, MO is approximately 630 ft tall. How many U.S. dimes would be in a stack of the same

miskamm [114]

Answer:

142240

Explanation:

We are told in the question:

Height of Gateway Arch in St. Louis, MO = 630ft

We are asked, how many U.S. dimes would be in a stack of the same

height when 1 dime is 1.35 mm thick.

Step 1

Convert height in ft to mm

1 ft = 304.8 mm

630ft =

Cross Multiply

630ft × 304.8mm/1ft

= 192024 mm.

Step 2

To find how many US dimes would be in a stack of the same height

= Total thickness/ Thickness of 1 US dime

= 192024 mm/1.35mm

= 142240

Therefore, the number of dimes that would be in a stack of the same

height is 142240

6 0

2 years ago