All categories

3 years ago

What molecule makes up 3/4s of the surface of Earth? A: C6H12O6 B:CO2 C: H2O D: NaCl

Chemistry

2 answers:

algol [13]3 years ago

6 0

Je suis presque sûr que c'est C: H20

Serga [27]3 years ago

4 0

Answer: H2O
Explanation: Yes

You might be interested in

In a ________ change, such as a change of state, the substance as a whole changes, but its underlying structure remain the same.

pav-90 [236]

Answer:

Im pretty sure it is chemical change

4 0

2 years ago

Please help me with chemistry

vodka [1.7K]

Table Giving Answer

Element Atomic mass % Amount

Mg_24 24 79 18.96

Mg_25 25 10 2.5

Mg_26 26 11 2.86

Total 24.32

Discussion

The method of calculation for this table, which was done in Excel (a spread sheet) is shown below. Assume that there is 100 grams of material of "pure" magnesium. What is it's mass?

Sample Calculation

The the sample atomic mass = 24

Mass = % * sample atomic mass

Mass = 79% * 24

Mass = (79/100) * 24

Mass = 18.96

Note

The other two elements are found exactly the same as the sample calculation.

Then all you do is add the 3 masses together.

Answer

The mass of Mg to 1 decimal place is 24.3 <<<< Answer.

7 0

3 years ago

Which of the following information is necessary to describe an object's motion?

Zepler [3.9K]

Answer: The correct option is B.

Explanation: To describe the motion of an object, we use the equations of motion.

$v=u+at$
$s=ut+\frac{1}{2}at^2$
$2as=v^2-u^2$

From the above equations, we require position, speed and direction through which we an calculate the displacement, velocity and acceleration.

To calculate the complete motion of an object, we require all the three factors.

Hence, the correct option is B.

8 0

2 years ago

Read 2 more answers

Modify the given fatty acid so that it represents the 18‑carbon fatty acid designated 18:2(Δ9,12). Draw any double bonds in the

Mekhanik [1.2K]

Answer:

See explanation

Explanation:

In this case, we have to remember the meaning of the nomenclature "18:2Δ9,12". Where 18 is the number of carbon atoms, 2 is the number of double bonds, and the numbers successive to Δ "delta" the position of the double bonds starting to count from the carboxylic -COOH end of the molecule.

In other words, the main functional group is a carboxylic acid. We have a total of 18 carbons. Additionally, we have 2 double bonds. On carbons 9 and 12.

Lets see figure 1

I hope it helps!

5 0

3 years ago

Help please. 15.0 moles of gas are in a 3.00L tank at 23.4∘C . Calculate the difference in pressure between methane and an ideal

CaHeK987 [17]

Using PV=nRT or the ideal gas equation, we substitute n= 15.0 moles of gas, V= 3.00L, R equal to 0.0821 L atm/ mol K and T= 296.55 K and get P equal to 121.73 atm. The Van der waals equation is (P + n^2a/V^2)*(V-nb) = nRT. Substituting a=2.300L2⋅atm/mol2 and b=0.0430 L/mol, P is equal to 97.57 atm. The difference is 121.73 atm- 97.57 atm equal to 24.16 atm.

3 0

3 years ago