19. place moth balls in the closet and observe after several days.
20. whenever wax or a candle burns it turns from solid to liquid but again at room temperature it turns to solid
21. evaporation, condensation, precipitation
22. it produces new substances
23. vinegar Bubbles when baking soda is added
24. steam
The soft, clay-rich rock known as shale, when subjected to pressure becomes a harder rock called slate. ... Even coal can be metamorphosed; bituminous (soft) coal, a sedimentary rock, can be changed into anthracite, or hard coal.
Answer:
4KO₂ + 2CO₂ -> 2K₂CO₃ + 3O₂
<u> Step 1: Find the moles of O₂.</u>
n(O₂) = mass/ Mr.
n(O₂) = 100 / 32 = 3.125 mol
<u>Step 2: Find the ratio between KO₂ and O₂.</u>
<u>KO₂ </u> : <u> O₂</u>
4 : 3
4/3 : 1
(4*3125)/3 : 3.125
=4.167 mol of KO₂
Thus now we know, to produce 100 g of O₂, we need 4.167mol of KO₂
<u>Step 3: Find the mass of KO₂:</u>
<u />
mass = mol * Mr. (KO₂)
Mass = 4.167* 71.1
Mass = 296.25 g
The correct answer would be... Scientific
Answer:
55,000,000
Explanation:
550 hectometers [hm] = 55,000,000 millimeters [mm]
