An ice sculpture melts into a puddle of water. What is true of this reaction?

A lake has been infected by some type of new algae that is unknown. Every single day the amount of surface area that the algae t

FrozenT [24]

Answer:

It takes 86 days take to cover half of the lake

Explanation:

In the day #1, the amount of the algae is X,

In the day #2 is 2X

In the day #3 is 2*2*X = X*2²

...

In the day #n the amount of the algae is X*2^(n-1)

Assuming X = 1m³. In the day 87, the area infected was:

1m³*2^(87-1)

7.74x10²⁵m³ is the total area of the lake

the half of this amount is 3.87x10²⁵m³

The time transcurred is:

3.87x10²⁵m³ = 1m³*2^(n-1)

Multiplying for 5 in each side:

ln (3.87x10²⁵) = ln (2^(n-1))

58.9175 = n-1 * 0.6931

85 = n-1

86 = n

<h3>It takes 86 days take to cover half of the lake</h3>

4 0

3 years ago

Explain what WHMIS is

White raven [17]

Workplace Hazardous Materials Information System is the answer to this question. Hope it helps :)

7 0

3 years ago

If 97.3 L of NO2 forms measured at 35 C and 632 mm Hg. What is the percent yield?

enyata [817]

a. Use PV = nRT and solve for n = number of mols O2.
mols NO = grams/molar mass = ?

Using the coefficients in the balanced equation, convert mols O2 to mols NO2. Do the same for mols NO to mols NO2. It is likely that the two values will not be the same which means one is wrong; the correct value in LR (limiting reagent) problems is ALWAYS the smaller value and the reagent producing that value is the LR.

b.
Using the smaller value for mols NO2 from part a, substitute for n in PV = nRT, use the conditions listed in part b, and solve for V in liters. This will give you the theoretical yield (YY)in liters. The actual yield at these same conditions (AY) is 84.8 L.

and % will be 60%.

3 0

3 years ago

Question 20 (3 points) Why is the moon visible? Question 20 options: It is on fire. It reflects sunlight. Earth lights it up. It

alexgriva [62]

20. Answer is "it reflects sunlight".

The moon is not a star as sun. Hence, moon can't produce light by itself. The only reason that we can see the moon is it reflects the sunlight. According to the distance from the sun to the moon, the light reflection can be varied.

21. Answer is "Jupiter".

Asteroid belt is a region which is located between Mars and Jupiter and consists of asteroids and minor planets. This asteroid belt has the 4% as the mass of our moon. Due to the Jupiter's strong gravity, it is prevented a forming of new planet by this asteroid belt.

22. Answer is "they are equal".

The period of revolution is the time which is taken by a mass to go completely one round around another mass. For moon, the period of revolution is 27 days.
The period of rotation is the time taken by a mass to complete one round around its own axis. It is about 27 days for moon.

23. Answer is "The moon is in Earth's shadow".

Lunar eclipse happens when Sun, Earth and moon are directly aligned each other and Earth is located in between the Sun and the moon. Then the moon is covered by the Earth's shadow.

24. Answer is "In a solar eclipse, it is Earth that is caught in the umbra of the moon. In a lunar eclipse, it is the moon that is caught in the umbra of Earth".

In total lunar eclipse, Earth is located between Sun and the moon and they are directly aligned to each other. The moon is totally covered with the Earth's shadow.
Total solar eclipse can be seen when the moon is located between sun and Earth by completely covering the sun.

25. According to the given choices, we can get "Apollo" as the answer.

Apollo 8 is the first manned mission to the moon. From that there were several manned mission including first manned landing on the moon. The Apollo program was conducted by USA.