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Over [174]
3 years ago
14

Please help me please

Chemistry
2 answers:
AnnZ [28]3 years ago
8 0

Answer:

20 is b and 21 is a.

Ludmilka [50]3 years ago
7 0

Answer:

b

Explanation:

i read this once and remember,trust me!

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In Latin, the word arthropod means jointed foot.
lord [1]

Answer: a pair of antennae

Explanation:

6 0
2 years ago
14.7 grams of magnesium reacts completely with 9.7 grams of oxygen to form magnesium oxide (MgO). What is the percent compositio
swat32
The answer is 60.3% magnesium, 39.7% oxygen.
Solution:
The chemical equation for the reaction is 2 Mg + O2 → 2 MgO.
Since magnesium reacts completely with oxygen, it is the limiting reactant in the reaction. Hence, we can use the number of moles of magnesium to get the mass of MgO produced:
     moles of magnesium = 14.7g / 24.305g mol-1
                                       = 0.6048 mol

     mass of MgO = 0.6048mol Mg(2 mol MgO/2mol Mg)(40.3044g MgO/1 mol MgO) 
                           = 24.376g MgO

We can now solve for the percentage of magnesium:
     % Mg = (14.7g Mg / 24.376g MgO)*100% = 60.3%

We also use the number of moles of magnesium to get the mass of oxygen consumed in the reaction:
     mass of O2 =  0.6048 mol Mg (1mol O2 / 2mol Mg) (31.998g / 1mol O2) 
                        = 9.676g

The percentage of oxygen is therefore
     % O2 = (9.676g O2 / 24.376g MgO)*100%
               = 39.7%
Notice that we can just subtract the magnesium's percentage from 100% to get 
     % O2 = 100% - 60.3% = 39.7%
5 0
3 years ago
Which determines how atoms combine to form molecules?
arlik [135]
Will be letter E cause all of them can combine molecule
7 0
3 years ago
Which of the following is NOT a derived unit?<br><br>a) <img src="https://tex.z-dn.net/?f=cm%5E%7B3%7D" id="TexFormula1" title="
seraphim [82]

Answer:

c) kg

Explanation:

Kilograms stands alone. It has to be hooked up to another unit for it to be a derived unit.

I am joyous to assist you anytime.

4 0
3 years ago
Read 2 more answers
Which of the following statements regarding glucose is FALSE?a) Glucose is the main component of starch and glycogen.b) Glucose
marishachu [46]

Answer:

The correct option is C.

Explanation:

Carbohydrates are one of the macro molecules that are consumed by living organisms. The end product of carbohydrate is glucose. Glucose is a very important fuel that the body cells used to produce energy, which they use to carry out their daily activities. Glucose is also known as blood sugar and it is the only fuel that living cells can use for the production of ATP. Other food macro molecules such as lipids and proteins can also be converted to glucose if there is a need for that. Glucose is always stored in the body in form of glycogen.

The statement given in option C about glucose is wrong because glucose is a monosaccharide and not a disaccharide.

8 0
3 years ago
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