Answer:
i added this table for some help
Explanation:
here are some examples
<u>metals:</u>They are hard and shiny, strong, and easy to shape. They are used for many industrial purposes. This group includes iron, gold, silver, chromium, nickel, and copper, some of which are also noble metals.
<u>non-metals:</u>a chemical element (as boron, carbon, or nitrogen) that lacks the characteristics of a metal and that is able to form anions, acidic oxides, acids, and stable compounds with hydrogen.
<u>metalloids:</u>Physical properties are usually those that can be observed using our senses such as color, luster, freezing point, boiling point, melting point, density, hardness and odor. Metalloids have mixed properties which are difficult to characterize.
Answer:
The answer to your question is 245.9 g of Fe₂O₃
Explanation:
Data
grams of Fe₂O₃ = ?
grams of Fe = 172 g
Balanced chemical reaction
Fe₂O₃ + 3H₂ ⇒ 2Fe + 3H₂O
Process
1.- Calculate the molar mass of of Iron Oxide and Iron
Fe₂O₃ = (2 x 56) + (3 x 16) = 112 + 48 = 160 g
2Fe = 2 x 56 = 112 g
2.- Use proportions and cross multiplication to solve this problem
160 g of Fe₂O₃ --------------- 112 g of Fe
x ---------------- 172 g of Fe
x = (172 x 160)/112
x = 27520/112
x = 245.9 g of Fe₂O₃
-20.16 KJ of heat are released by the reaction of 25.0 g of Na2O2.
Explanation:
Given:
mass of Na2O2 = 25 grams
atomic mass of Na2O2 = 78 gram/mole
number of mole = 
= 
=0. 32 moles
The balanced equation for the reaction:
2 Na2O2(s) + 2 H2O(l) → 4 NaOH(aq) + O2(g) ∆Hο = −126 kJ
It can be seen that 126 KJ of energy is released when 2 moles of Na2O2 undergoes reaction.
similarly 0.3 moles of Na2O2 on reaction would give:
= 
x = 
= -20.16 KJ
Thus, - 20.16 KJ of energy will be released.
