All categories

3 years ago

Calculate the amount of grams of water that was used when 5525J of energy was used to boil this amount of water.

Chemistry

1 answer:

djverab [1.8K]3 years ago

4 0

Answer:

2.445 g

Explanation:

Step 1: Given and required data

Energy in the form of heat required to boil the water (Q): 5525 J

Latent heat of vaporization of water (∆H°vap): 2260 J/g

Mass of water (m): ?

Step 2: Calculate the mass of water

We will use the following expression.

Q = ∆H°vap × m

m = Q / ∆H°vap

m = 5525 J / (2260 J/g)

m = 2.445 g

You might be interested in

A sample of P2Cl5 contains 179 g of phosphorous, how many grams of chlorine are present? Please show step by step thx!

natima [27]

Answer:

About 512 g.

Explanation:

We are given a sample of P₂Cl₅ that contains 179 grams of phosphorus, and we want to determine the grams of chlroine that is present.

Thus, we can convert from grams of phosphorus to moles of phosphorus, moles of phosphorus to moles of chlorine, and moles of chlorine to grams of chlorine.

From the formula, there are two moles of P for every five moles of Cl. The molecular weights of P and Cl are 30.97 g/mol and 35.45 g/mol, respectively. Hence:

$\displaystyle 179\text{ g P} \cdot \frac{1\text{ mol P}}{30.97\text{ g P}} \cdot \frac{5\text{ mol Cl}}{2\text{ mol P}} \cdot \frac{35.45\text{ g Cl}}{1\text{ mol Cl}} = 512\text{ g Cl}$

In conclusion, there is about 512 grams of chlorine present in the sample.

Alternatively, we can mass percentages. The mass percent of phosphorus in P₂Cl₅ is:

$\displaystyle \% \text{P} = \frac{2(30.97)}{5(35.45) + 2(30.97)} = 25.90\%$

Because there are 179 grams of phosphorus, the total amount of sample present is:

$\displaystyle \begin{aligned} 25.90\% \cdot m_T & = 179\text{ g P} \\ \\ m_T & = 691.1 \text{ g}\end{aligned}$

Therefore, the amount of chlorine present is 691.1 g - 179 g, or about 512 g, in agreement with our above answer.

8 0

2 years ago

Light travels extremely rapidly (c = 3.00×108 m/s ). Suppose you had to travel 40 miles to work every day. If you traveled at th

Reptile [31]

Given , Speed of light = 3 × 10⁸ m/s
Distance = 40 × 1.61× 1000 m
= 264400 m
We know that, speed = distance/time
so, time = distance/speed
t = 264400 / 3 × 10⁸
t = 0.00881333 sec Approx
The answer is 0.00881333 sec Approx

7 0

3 years ago

The rate constant for this zero‑order reaction is 0.0240 M ⋅ s − 1 0.0240 M·s−1 at 300 ∘ C. 300 ∘C. A ⟶ products A⟶products How

maw [93]

Answer: It will take for the concentration of A to decrease from 0.900 M to 0.210 M is 28.75 s

Explanation:

Zero order reaction : A reaction is said to be of zero order if the rate is independent of the concentration of the reactants, that means the rate is directly proportional to the zeroth power of the concentration of the reactants.

Expression for the zero order kinetics:

$[A]=-kt+[A]_o$

where [A] = concentration left after time t = 0.210 M

$[A]_o$ = initial concentration = 0.900 M

k= rate constant = $0.0240Ms^{-1}$

t = time for reaction = ?

$0.210=-0.0240\times t+0.900$

$t=28.75s$

Thus it will take for the concentration of A to decrease from 0.900 M to 0.210 M is 28.75 s

7 0

3 years ago

Does a light with low frequency and long wavelength have a lot or little energy?

Rudik [331]

The lower the frequncy the longer the wavelength the longer the wavelength whoch would probably give you more energy.

if im incorrect im truly sorry

7 0

3 years ago

Why potasium more reactive than lithium and sodium

frez [133]

So potassium is more reactive than lithium because the outer electron of a potassium atom is further from its nucleus than the outer electron of a lithium atom. Hope this answers the question. Have a nice day. Feel free to ask more questions.

5 0

3 years ago