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2 years ago

Why are stars special sources of light?(2 points)

Chemistry

1 answer:

Alex787 [66]2 years ago

8 0

Answer:

They give off their own light energy

Explanation:

I'm taking astronomy and I answered this questions not too long ago

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why are plasmas of great interest to scientists or manufacturers. descride 2 current uses of plasmas and describe 1 way scientis

Helga [31]

Answer:

Plasmas of great interest to scientists or manufacturers as

Plasma is electrically charged gases that contain considerable charged particles that can change the behavior of the substance.

Current uses of plasmas:

First, it is used to make semiconductors for different types of electronic equipment

Secondly, they're used in making transmitters for high-temperature films.

Way scientists and engineers hope to use plasmas in the future:

The scientists are hoping to use plasma in the future to get rid of all hazardous wastes through a process called plasma gasification.

6 0

2 years ago

If you have 2.4L of SO2 gas (at STP) how many moles of sulfur dioxide do you have?

Andru [333]

Answer:

0.107 mole of SO2.

Explanation:

1 mole of a gas occupy 22.4 L at standard temperature and pressure (STP).

With the above information, we can simply calculate the number of mole of SO2 that will occupy 2.4 L at STP.

This can be obtained as follow:

22.4 L contains 1 mole of SO2.

Therefore, 2.4 L will contain = 2.4/22.4 = 0.107 mole of SO2.

Therefore, 0.107 mole of SO2 is present in 2.4 L at STP.

4 0

2 years ago

What is the percent by mass of oxygen in carbon dioxide (CO2)?

wariber [46]

Answer:

= 72.73%

Explanation:

The percentage by mass of an element is given by;

% element = total mass of element in compounds/molar mass of compound × 100

The mass of oxygen in carbon dioxide = 32 g

Molar mass of CO2 = 44 g

Therefore;

% of O2 = 32/44 × 100%

= 72.73%

8 0

2 years ago

An object with a mass of 5.0 kg accelerates 8.0 m/s2 when an unknown force is applied to it. What is the amount of the force?

atroni [7]

The correct amount of force i believe is
f= 40 newton
i got the answer by using the formula below
force = mass x acceleration
f=5kg *8.0 m/s^2

7 0

2 years ago

The nonvolatile, nonelectrolyte estrogen (estradiol), C18H24O2 (272.40 g/mol), is soluble in chloroform CHCl3.

Artist 52 [7]

Answer: The molarity of solution is 0.274 M and the osmotic pressure of the solution is 6.70 atm

Explanation:

To calculate the molarity of the solution, we use the equation:

$\text{Molarity of the solution}=\frac{\text{Mass of solute}\times 1000}{\text{Molar mass of solute}\times \text{Volume of solution (in mL)}}$

We are given:

Given mass of estrogen = 13.5 g

Molar mass of estrogen = 272.40 g/mol

Volume of solution = 181 mL

Putting values in above equation, we get:

$\text{Molarity of solution}=\frac{13.5\times 1000}{272.40\times 181}\\\\\text{Molarity of solution}=0.274M$

Hence, the molarity of solution is 0.274 M

To calculate the osmotic pressure of the solution, we use the equation:

$\pi=iMRT$

where,

$\pi$ = osmotic pressure of the solution = ?

i = Van't hoff factor = 1 (for non-electrolytes)

M = molarity of solute = 0.274 M

R = Gas constant = $0.0821\text{ L atm }mol^{-1}K^{-1}$

T = temperature of the solution = 298 K

Putting values in above equation, we get:

$\pi=1\times 0.274mol/L\times 0.0821\text{ L.atm }mol^{-1}K^{-1}\times 298K\\\\\pi=6.70atm$

Hence, the osmotic pressure of the solution is 6.70 atm

8 0

2 years ago