Answer:
O.
Explanation:
- The element which is oxidized is the element that losses electrons and its oxidation state be more positive.
- The element which is reduced is the element that gain electrons and its oxidation state be more negative.
<em> O goes from 0 to -2, so, it is the element that is reduced.</em>
Answer:
Approximately 
.
Explanation:
This question can be solved using Hess's Law.
Start by considering: how can the first three reactions (with known 
values) be combined to produce the reaction 
?
Here's one possible combination:
- Include the first reaction once, without inverting.
- Invert the second reaction and include it once.
- Include the third reaction after multiplying all its coefficients by two.
In other words, if 
, 
, and 
denote the three reactions with know values, respectively, then 
will give the required reaction .
By Hess's Law, the value of the reaction will thus be:
.
Answer:
5.4 tonnes.
Explanation:
The first step is to find the molar mass of Al2O3. Aluminum has a molar mass of about 27 and oxygen has a molar mass of about 16, so 2(27)+3(16)= 102g/mol=0.102kg/mol. 10200kg/0.102kg/mol=100,000 moles of Al2O3 in 10.2 tonnes. Multiplying this by the molar mass of the two aluminums, you get a total of 54*100,000=5400000g=5400kg=5.4 tonnes. Hope this helps!
Answer:
c.all atoms have the same arrangement for electrons
