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Which of these statements is true about photons?

Yuliya22 [10]

Answer: it’s a I believe

Explanation: protons are smaller then atoms which means they have less mass

6 0

2 years ago

In a lab, silver nitrate,AgNO₃, is dissolved in water until no solid is observed in the container. Then, a solution of sodium ch

leva [86]

Answer:

The answer to your question is: A, C, E

Explanation:

After reading the information given, we can conclude that both reactants react to form a new solid product and another product that do not precipitate.

The reaction is:

AgNO₃ + NaCl ⇒ AgCl + NaNO₃

a. Formation of a solid indicates that a chemical reaction occurred This option is correct, precipitation indicates that a changed occurred in the solution due to a chemical reaction.

b. The initial disappearance of silver nitrate in water indicates a chemical reaction occurred No, what is happing is that silver nitrate is dissolving in water, this process is a physical change because matter do not change its nature.

c. The color change of the solution indicates a chemical reaction occurred This option is true, when a color appears suggest the formation of a new product.

d. A chemical reaction occurred when silver nitrate was added to water

This option is not correct, in this process silver nitrate is dissolving in water but it is not a chemical reaction because matter does not change is nature.

e. A chemical reaction occurred when the solutions were combined This option is true because silver nitrate and sodium chloride react to form a new product (solid formation and change in color).

f. The lack of temperature change indicates a chemical reaction didn't occur This is false, some reactions do not need a change of color to happen.

6 0

2 years ago

If a plane is traveling300 mph how long will it take to travel 1800 miles

bonufazy [111]

My calculations say it'll take 600 hours???

5 0

3 years ago

A sample of 9.00 grams of aluminum metal is added to an excess of hydrochloric acid. The volume of hydrogen gas produced at stan

marysya [2.9K]

Answer:

The volumen of hydrogen (H) is 11.22 L

Explanation:

The balanced reaction between the aluminum (Al) and the hydrochloric acid (HCl) is:

2Al(s) + 6HCl(l) --> 2AlCl3(ac) + 3H2(g)

It is a reduction-oxidation reaction.

At the beginning we have 9.00 grams of Al what represents an certain amount of moles. Then, we know the molar mass of Al is 26.9815 g/mol, so the moles content in 9.00 g of Al are :

9.00 g Al * (1 mol Al / 26.9815 g Al)= 0.33356 mol Al

Now, we have to conisdered the molar relation between the Al and H2, according to the balanced reaction performed above. That is 2:3 (Al:H2)

Then,

0.33356 mol Al * (3 mol H2/ 2mol Al) = 0.50034 mol H2

In this point, we can considered the H2 like a noble gas, because the question ask for standard temperature and pressure (0° C= 273.15K and 1 atm).

Let us remember the noble gases equation

PV=nRT

P: pressure

V: Volumen

n: number of moles

R: gases constant

T: temperature

For the volumen, the equation is:

V= (nRT/P)

Now: V= (0.50034 mol * 0.0821 (L*atm/K*mol) * 273.15 K)/ (1 atm)

V= 11.22 L

3 0

2 years ago

In yeast, ethanol is produced from glucose under anaerobic conditions. A cell‑free yeast extract is placed in a solution that co

12345 [234]

Answer:

650 mmol.

Explanation:

The equation for the fermentation of one mole of glucose is:

C₆H₁₂O₆ + 2 NAD⁺ + 2 ADP + 2 P i + 2 NADH → 2 EtOH + 2 ATP + 2 NADH + 2 NAD⁺

Since NAD⁺/NADH is used and regenerated, we can eliminate it from the equation:

C₆H₁₂O₆ + 2 ADP + 2 P i → 2 EtOH + 2 ATP

With the equation, we calculate the maximum amount of ethanol that could be obtained theoretically:

1000 mmol C₆H₁₂O₆ ------------ 2000 mmol EtOH

325 mmol C₆H₁₂O₆ ------------- x= 650 mmol EtOH

Therefore, the maximum amount of ethanol that could be produced is 650 mmol.

8 0

2 years ago