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2 years ago

Which of the following are true about both the sun and the stars? Choose the three correct answers.

Chemistry

1 answer:

Andrew [12]2 years ago

8 0

Answer:

D, F

Explanation:

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A 1,500 kg truck is towed sideways out of a mud-hole with a force of 15,000 N. What acceleration of the tow truck is needed to m

NeX [460]

Yes because without movement the tow truck will not be moved with 15,000 N

3 0

3 years ago

A piece of metal with a mass of 611 g is placed into a graduated cylinder that contains 25.1 ml of water, raising the water leve

jeka94

Mass of metal piece is 611 g and volume of graduated cylinder is 25.1 mL. When metal piece is placed in the graduated cylinder water level increases to 56.7 mL. The increase in volume is due to volume of metal piece that gets added to the volume of water.

Thus, volume of metal piece can be calculated by subtracting initial volume from the final one.

$V_{metal}=V_{final}-V_{initial}=(56.7-25.1)mL=31.6 mL$

Thus, volume of metal piece will be 31.6 mL. The mass of metal piece is given 611 g, density of metal can be calculated as follows:

$d=\frac{m}{V}=\frac{611 g}{31.6 mL}=19.33 g/mL$

Therefore, density of metal is 19.33 g/mL.

3 0

3 years ago

Give examples of how land resources are used in a city setting

poizon [28]

Answer:

Land resources such as gravel and bedrock are used to construct buildings, roads, and sidewalks. Land is also where city structures—such as buildings, roads, and sidewalks—are constructed. People use land resources such as bedrock and aggregate to construct buildings, roads, and sidewalks.

I hope this answer helps

5 0

3 years ago

Read 2 more answers

What is GMOs? ( Thanks btw )

Sunny_sXe [5.5K]

Answer:

living organisms whose genetic material has been artificially manipulated in a laboratory through genetic engineering

Explanation:

5 0

2 years ago

1 C8H10(l) +21/2O2(g) → 8CO2(g) + 5H2O(g), Hcomb= ? Hf for C8H10(l) = +49.0kJ/mol C8H10(l) Use the balanced combustion reaction

nikklg [1K]

Answer:

$H_{comb}=-4406kJ/mol$

Explanation:

Hello,

In this case, the enthalpy of combustion is understood as the energy released when one mole of fuel, in this case octene, is burned in the presence of oxygen and is computed with the enthalpies of formation of the fuel, carbon dioxide and water as shown below (oxygen is circumvented as it is a pure element):

$H_{comb}=8*\Delta _fH_{CO_2}+5\Delta _fH_{H_2O}-\Delta _fH_{C_8H_{10}}$

Thus, since we already know the enthalpy of combustion of the fuel, for carbon and water we have -393.5 and -241.8 kJ/mol respectively, thereby, the enthalpy of combustion turns out:

$H_{comb}=8*(-393.5kJ/mol)+5(-241.8kJ/mol)-49.0kJ/mol\\\\H_{comb}=-4406kJ/mol$

Best regards.

4 0

3 years ago