All categories

3 years ago

What happens to temperature and kinetic energy of particles during a change of state

1 answer:

3 0

When a substance is changing state, its temperature remains constant. This is because energy is used to increase/decrease kinetic energy of the molecules of the substance, increasing/decreasing the inter-molecular distance and overcoming the energy bonds present between the molecules. Therefore, no energy is used to raise the temperature of the substance and therefore it remains constant

You might be interested in

A sample of sodium sulfite has a mass of 2.80 g.

Gnom [1K]

Answer:

For a: The number of sodium ions in given amount of sodium sulfite are $2.65\times 10^{22}$

For b: The number of sulfite ions in given amount of sodium sulfite are $1.325\times 10^{22}$

For c: The mass of one formula unit of sodium ions is $2.09\times 10^{-22}$ grams

Explanation:

The chemical formula of sodium sulfite is $Na_2SO_3$ . It is formed by the combination of 2 sodium $(Na^+)$ ions and 1 sulfite $(SO_3^{2-})$ ions

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$

Given mass of sodium sulfite = 2.80 g

Molar mass of sodium sulfite = 126 g/mol

Putting values in above equation, we get:

$\text{Moles of sodium sulfite}=\frac{2.80g}{126g/mol}=0.022mol$

For a:

Moles of sodium ions in sodium sulfite = (2 × 0.022) moles

According to mole concept:

1 mole of a compound contains $6.022\times 10^{23}$ number of particles

So, 0.022 moles of sodium sulfite will contain = $(2\times 0.022\times 6.022\times 10^{23})=2.65\times 10^{22}$ number of sodium ions

Hence, the number of sodium ions in given amount of sodium sulfite are $2.65\times 10^{22}$

For b:

Moles of sulfite ions in sodium sulfite = (1 × 0.022) moles

According to mole concept:

1 mole of a compound contains $6.022\times 10^{23}$ number of particles

So, 0.022 moles of sodium sulfite will contain = $(1\times 0.022\times 6.022\times 10^{23})=1.325\times 10^{22}$ number of sulfite ions

Hence, the number of sulfite ions in given amount of sodium sulfite are $1.325\times 10^{22}$

For c:

Molar mass of sodium sulfite = 126 g/mol

According to mole concept:

$6.022\times 10^{23}$ number of formula units are present in 1 mole of a compound

Or, $6.022\times 10^{23}$ number of formula units of sodium sulfite have a mass of 126 grams

So, 1 formula unit of sodium sulfite will have a mass of = $\frac{126}{6.022\times 10^{23}}\times 1=2.09\times 10^{-22}g$

Hence, the mass of one formula unit of sodium ions is $2.09\times 10^{-22}$ grams

7 0

3 years ago

Calculate the volume of liquid in the tank sketched below. Give your answer in liters, and round to the nearest 0.1 L.

wariber [46]

Answer:

1.3 L

Explanation:

The volume of a rectangular cube can be calculated using the following formula:

Volume (L) = length (cm) x width (cm) x height (cm)

Keep in mind that 1 L = 1,000 cm³.

Before you can plug the values into the equation, you need to make sure they all have the same unit. Since the length is in meters (m), you need to first convert it to centimeters.

1 meter = 100 cm

0.159 m 100 cm
--------------- x ---------------- = 15.9 cm
1 m

Now, you can solve for the volume. To find the answer is the unit liters, you need to divide the volume by 1,000.

Volume = l x w x h

Volume = 15.9 cm x 10.5 cm x 7.7 cm

Volume = 1,285.5 cm³

Volume = 1.2855 L ------> Volume = 1.3 L

7 0

1 year ago

The temperature of a star is 6000K and its luminosity is 1000. Which type of star is it?

Lorico [155]

Answer:

Its probably none of those.

Explanation:

White dwarf temperatures can exceed 100,000 Kelvin according to NASA (that's about 179,500 degrees Fahrenheit). Despite these sweltering temperatures, white dwarfs have a low luminosity as they're so small in size according to NMSU.

4 0

1 year ago

At equilibrium, ________. At equilibrium, ________. all chemical reactions have ceased the rate constants of the forward and rev

balandron [24]

Answer:

At equilibrium, the rate of the forward, and the reverse reactions are equal.

Explanation:

In an equilibrium chemical reaction, the rate of forward reaction, is equal to the rate of reverse reaction. Note that the reactions does not cease at equilibrium, but rather, the reactants are converted to product, at the same rate at which the product is also being converted into the reactants in the reaction. When chemical equilibrium is reached, a careful calculation of the value of equilibrium constant is approximately equal to 1.

NB: If the value of equilibrium constant is far far greater than 1, then the reaction will favors more of the forward reaction, and if far far less than 1, the reaction will favor more of the reverse reaction.

6 0

2 years ago

Explain if the efficiency of a machine can ever be greater than 100%?

Marizza181 [45]

You should download Socratic with a good app!

3 0

3 years ago

Read 2 more answers