Fossils provide evidence that

1 answer:

katrin2010 [14]3 years ago

7 0

Of these options, I'd say the third choice or "Many species of organisms that lived long ago are now extinct". I hope this helps :)

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Calculate the mass of aluminum in 500 g of Al(C2H3O2)3

Luden [163]

Answer: 66.2 g

Explanation:

1) The ratio of Al in the molecule is 1 mol to 1 mol .

2) The mass of 1 mol of molecules of Al (CH2H3O2)3 is the molar mass of the compound.

3) You calculate the molar mass of the compound using the atomic masses of each atom, in this way:

Al: 27 g/mol
C: 2 * 3 * 12 g/mol = 72 g/mol
H: 3 * 3 * 1 g/mol = 9 g/mol
O: 2 * 3 * 16 g/mol = 96 g/mol

Molar mass = 27 g/mol + 72 g/mol + 9 g/mol + 96 g/mol = 204 g/mol

4) Set a proportion:

27 g/mol x
-------------------- = ----------
204 g/mol 500 g

5) Solve for x:

x = 500 g * 27 g/mol / 204 g/mol = 66.2 g

5 0

3 years ago

Draw the structural formula of the major product of the reaction of (S)-2,2,3-trimethyloxirane with MeOH, H . Use the wedge/hash

Katarina [22]

Answer:

(S)-3-methoxy-3-methylbutan-2-ol

Explanation:

In this case, we have an epoxide opening in acid medium. The first step then is the protonation of the oxygen. Then the epoxide is broken to generate the most stable carbocation. The nucleophile ( $CH_3OH$ ) will attack the carbocation generating a new bond. Finally, the oxygen is deprotonated to obtain an ether functional group and we will obtain the molecule (S)-3-methoxy-3-methylbutan-2-ol.

See figure 1

I hope it helps!

8 0

3 years ago

Why is stainless steel harder than pure iron

lord [1]

Something made of pure iron is softer than steel because the atoms can slip over one another. If other atoms like carbon are added, they are different from iron atoms and stop the iron atoms from sliding apart so easily. This makes the metal stronger and harder.

3 0

3 years ago

Read 2 more answers

• 1) The pressure of a sample of gas in a 2.00-L container is 876 mmHg.

kifflom [539]

Answer:

4380 mmHg

Explanation:

Boyle's Law can be used to explain the relationship between pressure and volume of an ideal gas. The pressure is inversely related to volume, so if volume decrease the pressure will increase. It can be expressed in the equation as:

P1V1=P2V2

In this question, the first condition is 2L volume and 876 mmHg pressure. Then the system changed into the second condition where the volume is 400ml and the pressure is unknown. The pressure will be:

P1V1= P2V2

876 mmHg * 2L = P2 * 400ml /(1000ml/L)

P2= 876 mmHg * 2L / 0.4L

P2= 4380 mmHg

5 0

3 years ago

How do i calculate the mass of CO2 emitted per Kj of heat produced in a combustion reaction?

Alexxandr [17]

methanol:

1 mole CH3 OH --> produces --> 1 mole CO2

1 mole CO2 has a molar mass of 44.01 gh/mole

your set up is:
(44.01 g CO2) / -726.5kJ = 0.06058g

your answer 0.06058 grams of CO2 produced per kJ released.

6 0

4 years ago