Answer:
D 4,3,2
Explanation:
4 Co + 3 O2 ----> 2 Co2O3
Answer:
Because it only needs one more electron to get to a full valence shell (8), so it really wants it and is pulling other electrons in. It also has to do with needing one more electron to fill the 2p shell. It is a small element which means its electrons are pulled tightly to the nucleus.
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Explanation:
Answer:
The process where substance react with oxygen is called combustion.
Explanation:
When substance react with oxygen combustion is occur. The substance which burned is called fuel and in this process large amount of heat is released to the surrounding. It is exothermic process.
For example:
4Li + O₂ → 2Li₂O
2Mg + O₂ → 2MgO
S + O₂ → SO₂
The product which is formed as a result of combustion reaction are called oxides.
In given examples we can see that lithium, magnesium and sulfur react with oxygen and product formed is oxides of respective elements such as lithium oxide ( Li₂O), magnesium oxide (MgO) and sulfur oxide ( SO₂ ).
Answer:
(a) 
(b)
(c) 
Explanation:
Hello,
(a) In this case, with the given formula we easily compute the mass of gold contained in the sovereign as shown below:
(b) Now, by knowing the density of gold and copper, 19.32 and 8.94 g/cm³ respectively, we compute each volume, by also knowing that the rest of the coin contains copper:
(c) Finally, the volume is computed by dividing the total mass over the total volume containing both gold and copper:
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