Answer: With the first quarter moon, the Moon is "waxing", which means getting larger. with the third quarter moon, the Moon is "waning", which means getting smaller.
Explanation: In each case, the Moon is half lit ---- first quarter moon is when it is increasing and the third quarter moon is decreasing
Hope this helped! :)
Answer: an ice pack getting cold (due to ammonium nitrate dissolving in water inside the pack)
Explanation:
Endothermic reactions: These are the reactions in which energy is required in the reaction. The energy of the products are more than the energy of the reactants.
Exothermic reactions: These are the reactions in which energy is released in the reaction. The energy of the products is less than the energy of the reactants.
a) water droplets condensing on a soda can on a hot summer day : As the gaseous molecules are changing into liquid phase, energy is released and is exothermic
b) an ice pack getting cold (due to ammonium nitrate dissolving in water inside the pack) : As the temperature is decreasing , energy is absorbed by the surroundings and thus is endothermic
c) thermite reaction between iron(III) oxide and aluminium (spectacular flames are observed) : As flames are produced, the energy is released and thus is exothermic
d) freezing water to make ice cubes : As the liquid molecules are changing into solid phase, energy is released and is exothermic
<span>"The theory states that pressure increases with temperature." that is the correct statement I believe.
hope this helps! :-)</span>
The empirical formula is Fe₃O₄.
The empirical formula is the <em>simplest whole-number ratio of atoms</em> in a compound.
The ratio of atoms is the same as the ratio of moles, so our job is to calculate the molar ratio of Fe to O.
I like to summarize the calculations in a table.
<u>Element</u> <u>Moles</u> <u>Ratio</u>¹ <u>×3</u>² <u>Integers</u>³
Fe 0.77 1 3 3
O 1.0 1.3 3.9 4
¹ To get the molar ratio, you divide each number of moles by the smallest number (0.77).
² If the ratio is not close to an integer, multiply by a number (in this case, 3) to get numbers that are close to integers.
³ Round off these numbers to integers (3 and 4).
The empirical formula is Fe₃O₄.