All categories

3 years ago

Which of these best explains why the sun appears to move across the sky each day?

Chemistry

2 answers:

Crank3 years ago

8 0

I pretty sure is D, because earth rotates around the sun

ElenaW [278]3 years ago

4 0

Answer:

Explanation:

A is day and night, which is when we see the sun move

D is the 4 seasons

You might be interested in

Is CH3COOCH3 an acid or base?

Romashka-Z-Leto [24]

Answer:

acid

Explanation:

Methyl acetate, also known as MeOAc, acetic acid methyl ester or methyl ethanoate, is a carboxylate ester with the formula CH3COOCH3. It is a flammable liquid with a characteristically pleasant smell reminiscent of some glues and nail polish removers.

4 0

2 years ago

Read 2 more answers

Balance the combustion eqation; __C5H + __O2 ---> __CO2+__H2O

stira [4]

This equation C5H + O2 ---> CO2 + H2O has a mistake.

C5H is wrong. You missed the subscript of H.

I will do it for you assuming some subscript to show you the procedure, but you have to use the right equation to get the right balanced equation.

Assuming the tha combustion equation is C5H12 + O2 ---> CO2 + H2O

First you need to balance C, so you put a 5 before CO2 and get

C5H12 + O2 ---> 5CO2 + H2O

Now you count the hydrogens: 12 on the left and 2 on the right. So put a 6 before H2O and get:

C5H12 + O2 ---> 5CO2 + 6H2O

Now count the oxygens: 2 on the left and 16 on the right, so put an 8 on before O2:

=> C5H12 + 8O2 ---> 5CO2 + 6H2O.

You can verify that the equation is balanced

8 0

3 years ago

The equilibrium concentrations of the reactants and products are [ HA ] = 0.260 M [HA]=0.260 M , [ H + ] = 2.00 × 10 − 4 M [H+]=

ValentinkaMS [17]

Answer:

pKa of the acid HA with given equilibrium concentrations is 6.8

Explanation:

The dissolution reaction is:

HA ⇔ H⁺ + A⁻

So at equilibrium, Ka is calculated as below

Ka = [H⁺] x [A⁻] / [HA] = 2.00 x 10⁻⁴ x 2.00 x 10⁻⁴ / 0.260

= 15.38 x 10⁻⁸

Hence, by definition,

pKa = -log(Ka) = - log(15.38 x 10⁻⁸) = 6.813

7 0

3 years ago

Which of the following is not present in skeletal structures?

cupoosta [38]

Answer:

cartilage or soft tissue? you didn't give options :/

Explanation:

6 0

3 years ago

Reaction is

-Dominant- [34]

According to the task, you are proveded with patial pressure of CO2 and graphite, and here is complete solution for the task :
At first you have to find n1 =moles of CO2 and n2 which are moles of C
<span>The you go :
</span> $CO2(g) + C(s) \ \textless \ =\ \textgreater \ 2CO(g)$

n1 n2 0
-x -x +2x
$n1-x n2-x 2x Kp=P^2 (CO)/Pco2$
After that you have to use the formula $PV=nRT$
$Kp=(2x)^2/n1-x$
Then you have to solve x, and for that you have to use <span>RT/V
And to find total values:</span> $P(total)=n(total)*R*T/V$
I am absolutely sure that this would be helpful for you.

7 0

3 years ago