Which of the following could cause a change in state from a liquid to a solid?

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

Which statement describes the use of a flowchart?

castortr0y [4]

Answer: I believe it is B

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3 years ago

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The pressure on a sample of gas is increased from 1.0 atm to 3.0 atm. If the new volume is 0.52 L, find the original volume.

swat32

Answer: 1.56 ATM

Explanation: if we assume temperature is constant, gas obeys

Boyles law pV= constant. Then p1·V1= p2·V2. And V1 = p2V2/p1

= 3.0 atm·0,52 l / 1.0 atm

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AB G C F G Y OBLAD

viktelen [127]

Blade resistance hair motion pull down

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M

vlada-n [284]

Answer:

El cocodrilo se arrastró durante 20.833 segundos.

Explanation:

El enunciado presenta omisiones y errores conceptuales. La forma correcta es la siguiente: "Un cocodrilo se arrastró 25 metros hacia la derecha con una rapidez promedio de 1.2 metros por segundo. ¿Cuántos segundos se arrastró el cocodrilo?"

Consideremos que el cocodrilo tiene un movimiento rectilíneo uniforme, el tiempo requerido para el recorrido se calcula con la siguiente ecuación cinemática:

$t = \frac{x}{v}$ (1)