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3 years ago

18. Which statement best describes the balanced chemical equation?

Chemistry

1 answer:

ch4aika [34]3 years ago

4 0

Answer:

It is endothermic and entropy increases.

Explanation:

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What is the volume of a solid with a mass of 17.4 g and a density of 0.934 g /cm cubed?

Anvisha [2.4K]

Answer:

18.6 g/cm^3

Explanation:

17.4g/0.934g/cm^3

(divide)

5 0

3 years ago

an engineer wishes to design a container that will hold 12.0 mol of ethane at a pressure no greater than 5.00x10*2 kPa and a tem

OleMash [197]

Answer:

The minimum volume of the container is 0.0649 cubic meters, which is the same as 64.9 liters.

Explanation:

Assume that ethane behaves as an ideal gas under these conditions.

By the ideal gas law,

$P\cdot V = n\cdot R\cdot T$ ,

$\displaystyle V = \frac{n\cdot R\cdot T}{P}$ .

where

$P$ is the pressure of the gas,
$V$ is the volume of the gas,
$n$ is the number of moles of particles in this gas,
$R$ is the ideal gas constant, and
$T$ is the absolute temperature of the gas (in degrees Kelvins.)

The numerical value of $R$ will be $8.314$ if $P$ , $V$ , and $T$ are in SI units. Convert these values to SI units:

$P =\rm 5.00\times 10^{2}\;kPa = 5.00\times 10^{2}\times 10^{3}\; Pa = 5.00\times 10^{5}\; Pa$ ;
$V$ shall be in cubic meters, $\rm m^{3}$ ;
$T = \rm 52.0 \textdegree C = (52.0 + 273.15)\; K = 325.15\; K$ .

Apply the ideal gas law:

$\displaystyle \begin{aligned}V &= \frac{n\cdot R\cdot T}{P}\\ &= \frac{12.0\times 8.314\times 325.15}{5.00\times 10^{5}}\\ &= \rm 0.0649\; m^{3} \\ &= \rm (0.0649\times 10^{3})\; L \\ &=\rm 64.9\; L\end{aligned}$ .

4 0

3 years ago

In a percentage composition investigation a compound was decomposed into its elements: 20.0 g of calcium, 6.0 g of carbon, and 2

inysia [295]

The percentage composition of this compound : 40%Ca, 12%C and 48%O

<h3>Further explanation</h3>

Given

20.0 g of calcium,

6.0 g of carbon,

and 24.0 g of oxygen.

Required

The percentage composition

Solution

Total mass of compound :

=mass calcium + mass carbon + mass oxygen

=20 g + 6 g + 24 g

=50 g

Percentage composition :

Ca-calcium

$\tt \dfrac{20}{50}\times 100\%=40\%$

C-carbon

$\tt \dfrac{6}{50}\times 100\%=12\%$

O-oxygen

$\tt \dfrac{24}{50}\times 100\%=48\%$

3 0

3 years ago

The earth receives 1.8 ✕ 1014 kj/s of solar energy. what mass of solar material is converted to energy over a 24-h period to pro

oksano4ka [1.4K]

Before starting, we will convert all the givens into standard units as follows:
1.8 * 10^14 KJ/sec = 1.8 * 10^14 * 1000 = 1.8 * 10^17 J/sec
24 hours = 24 * 60 * 60 = 86400 second

Now, we are given that:
The earth receives 1.8 * 10^17 J/sec. We will begin by calculating the total energy received by the earth in 24-hours
Total energy = 1.8 * 10^17 * 86400 = 1.5552 * 10^22 Joules

Then we will get the mass from the following rule:
E = m * c^2 where:
E is the total energy = 1.5552 * 10^22 Joules
m is the mass we need to find
c is the speed of light = 3 * 10^8 m/sec

Substitute with the givens to get the mass as follows:
1.5552 * 10^22 = m * (3*10^8)^2
m = 172800 kg

5 0

3 years ago

How many molecules are there in 2.3g Of carbon

Alexxandr [17]

Answer: 1.15x10²³ molecules C

Explanation: solution attached:

Convert mass of C to moles using its molar mass then multiply to the Avogadro's number.

8 0

3 years ago

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