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3 years ago

Which chemical symbol represents an element?

2 answers:

4 0

CO because it is the chemical symbol for the element cobalt whereas the rest are compound. H20 is water, CO2 is carbon dioxide and N2 is dinitrogen.

emmasim [6.3K]3 years ago

3 0

Answer: $N_2$

Explanation:

Element is a pure substance which is composed of atoms of similar elements.

It can not be decomposed into simpler constituents using chemical reactions.Example: Nitrogen $(N_2)$

Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.

It can be decomposed into simpler constituents using chemical reactions. Example: carbon dioxide $(CO_2)$ , water $(H_2O)$ , carbon monoxide $(CO)$

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Which of the following statements best describes why carbon can form a variety of organic compounds? Carbon atoms bond readily w

olga_2 [115]

Answer:
<span>Carbon readily forms covalent bonds with other carbon atoms.

Explanation:
As we know approximately more than 95 % compounds, either isolated, discovered or synthesized belongs to organic compounds containing carbon atoms.
This great diversity of organic compounds is due to following facts.

1) Catenation:
Carbon has a peculiar behavior of self linkage. This self linkage of one carbon with another is called as catenation. In this way carbon can form a long chain of carbon atom. A branching can also take place when one carbon is bonded further to three of four carbon atoms.

2) Isomerism:
Secondly the carbon containing compounds show isomerism. In which molecular formula is same but structural formula is different. For example molecular formula C</span>₅H₁₂ can make following compounds,

a) n-Pentane

b) 2-Methylbutane

c) 2,2-Dimethylpropane

3) Multiple Bonds:
Carbon can form multiple bonds i.e double bond like in alkenes and triple bonds like in alkyne.

Due to these factors carbon gets very high number of opportunities to form large number of compounds.

7 0

3 years ago

What would happen to an object if the force of gravity on Erath decreased by half

abruzzese [7]

Answer:

the object will float for a few seconds and most likely fall back down because it still has a little bit of gravity attached or it would float a few inches up but not too high in the air where its out of reach

Explanation:

6 0

3 years ago

An electric range burner weighing 699.0 grams is turned off after reaching a temperature of 482.0°C, and is allowed to cool down

jasenka [17]

Answer:

0.42 J/gºC

Explanation:

We'll begin by calculating the heat energy used to heat up the water. This can be obtained as follow:

Mass (M) of water = 560 g

Initial temperature (T₁) = 22.7 °C

Final temperature (T₂) = 80.3 °C.

Specific heat capacity (C) of water = 4.18 J/gºC

Heat (Q) absorbed =?

Q = MC(T₂ – T₁)

Q = 560 × 4.18 (80.3 – 22.7)

Q = 2340.8 × 57.6

Q = 134830.08 J

Finally, we shall determine the specific heat capacity of the burner. This can be obtained as follow:

Mass (M) of burner = 699 g

Initial temperature (T₁) = 482.0°C

Final temperature (T₂) = 22.7 °C

Heat (Q) evolved = – 134830.08 J

Specific heat capacity (C) of the burner =?

Q = MC(T₂ – T₁)

–134830.08 = 699 × C (22.7 – 482.0)

–134830.08 = 699 × C × –459.3

–134830.08 = –321050.7 × C

Divide both side by –321050.7

C = –134830.08 / –321050.7

C = 0.42 J/gºC

Therefore, the specific heat capacity of the burner is 0.42 J/gºC

8 0

3 years ago

What kind of energy is stored in bonds of molecules

Ne4ueva [31]

The answer to your question would more than likely be chemical energy, natural gas, and chemical energy. but I don't know what grade your in I'm in eighth if your below I know the answer. I'm pretty sure I had a question exactly like this last year but that was last year so if it's wrong sorry. I looked it up on Google to make sure

3 0

3 years ago

Select all steps below that you followed to practice laboratory safety during the experiment. used tongs or a test tube holder t

uysha [10]

Explanation:

Steps followed to practice laboratory safety during the experiment are as follows.

Used tongs or a test tube holder to hold materials over the Bunsen burner flame.
Wore gloves and goggles.
Made careful observations of the products and reactants.
Did not smell the gases produced.

When we heat a test tube over bunsen flame then the tube gets hot and when we hold it with bare hands then out hands will burn. Therefore, it is advised to hold test tube with the help of tongs or a holder so that our hands did not burn.

We should also wear gloves and goggles so that any acid would not spill directly on our hands, skin and eyes as it can affect or damage the skin severely.

Careful observations were made so that correct calculations about the experiment can be carried out.

It is also advised that we should not smell the gases produced but gases move freely from one place to another in a laboratory or any where else.

So, we can try to avoid it by covering our mouth with a cloth but we cannot stop it. If we keep on inhaling the gases produced in a laboratory then it can also lead to severe disease or defect in the human body.

8 0

3 years ago

Read 2 more answers