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sashaice [31]
3 years ago
12

A limited number of the many known elements comprise the largest portion of living matter. Group Elements A Calcium, Phosphorus,

Oxygen, Sulfur B Cobalt, Hydrogen, Oxygen, Nitrogen C с Helium, Oxygen, Sulfur, Carbon Hydrogen, Oxygen, Nitrogen, Carbon 1 1 Which group of elements above comprises the largest portion of living matter? A Group A B Group B C Group C D Group D​
Chemistry
1 answer:
notsponge [240]3 years ago
4 0

Answer:

Explanation:

Hydrogen oxygen nitrogen and carbon

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HgS + O2 → HgO + SO2
Igoryamba

Answer:

2HgS + 3O2 → 2HgO + 2SO2

The coefficients are: 2, 3, 2, 2

Explanation:

HgS + O2 → HgO + SO2

The equation can be balance as follow:

Put 3 in front of O2 as shown below:

HgS + 3O2 → HgO + SO2

Now we can see that there are 6 atoms of O on the left side of the equation and a total of 3 atoms on the right side. It can be balance by putting 2 in front of HgO and SO2 as shown below:

HgS + 3O2 → 2HgO + 2SO2

Now we have 2 atoms of both Hg and S on the right side and 1atom each on the left. It can be balance by putting 2 in front of HgS as shown below:

2HgS + 3O2 → 2HgO + 2SO2

Now the equation is balanced.

The coefficients are: 2, 3, 2, 2

The law of conservation of mass(matter) states that matter(mass) can neither be created nor destroyed during a chemical reaction but changes from one form to another. An unbalanced equation suggests that matter has been created or destroyed. While a balanced equation proofs that matter can never be created but changes to different form. This is the more reason we have count the atoms of an element on both side of the equation to see if they are balanced irrespective of the new form they assume in the product

5 0
3 years ago
If you start with 10ml of 0.75 m cu(no3)2 how much cu (s) in grams should be recovered in step #7
LenaWriter [7]
<span>0.48 grams. Not a well worded question since it's assuming I know the reactions. But I'll assume that since there's just 1 atom of copper per molecule of Cu(NO3)2, that the reaction will result in 1 atom of copper per molecule of Cu(NO3)2 used. With that in mind, we will have 0.010 l * 0.75 mol/l = 0.0075 moles of copper produced. To convert the amount in moles, multiply by the atomic weight of copper, which is 63.546 g/mol. So 0.0075 mol * 63.546 g/mol = 0.476595 g. Round the results to 2 significant figures, giving 0.48 grams.</span>
4 0
3 years ago
Density is the _____ of a certain ______
olga2289 [7]
I think the first blank is "solidity" and second is "object."
3 0
4 years ago
The valence electrons of a krypton (Kr) atom in the ground state are located in the
Korvikt [17]

I dont know the answer but i have some explanation for that question.

Since krypton is in the far right row of the periodic table, its outermost shell is full with eight electrons. This is one of the happy elements and has an electron configuration of 2-8-18-8.

8 0
2 years ago
How many grams of MgCl2 would be needed to make 5.3 liters of a 0.25 molar solution? Round your answer to the nearest 0.01,
GuDViN [60]

Answer: 126.1 grams of are needed to make 5.3 L of 0.25 M solution

Explanation:

Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.

To calculate the mass of solute for given molarity, we use the equation:

\text{Molarity of the solution}=\frac{\text{given mass of solute}}{\text {Molar mass of solute}\times \text{Volume of solution in L}}

0.25M=\frac{x}{95.2g/mol\times 5.3L}

x=126.1g

Thus 126.1 grams of are needed to make 5.3 L of 0.25 M solution

6 0
3 years ago
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