PLEASE HELP ME QUICK When an iron nail is ground into powder, its mass .
a. stays the same
b. decreases
c. increases
d. cannot be determined

When paper turns yellow-brown upon exposure to sunlight, what type of change is likely taking place?

a. a physical change
b. a chemical change
c. neither a physical change nor a chemical change
d. both a physical change and a chemical change

1.It stays the same

Explanation:

because its only the natural stature of it has changed

the correct answer is answer a. a mixture

no other options make sense

hope this

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  - sprinkles

the equation that correctly represent the reaction for formation of ammonia is

n2+ 3h2 → 2nh3 (answer d)

1 mole of nitrogen gas (n2) react with 3 moles of hydrogen gas (h2) to form 2 moles of ammonia ( nh3). this is in a process known as haber process were iron is used as a catalyst and reaction take place that a higher temperature and pressure. the process is exothermic hence energy is released.