Answer:
A. 2.9*10^24
B. 3.4*10^21
C. 1.2*10^25
D. 1.7*10^23
Explanation:
1 mol of any particle has 6.02*10^23.
A. 4.8 mol Cu* 6.02*10^23 (1/mol) ≈2.9*10^24
B. 5.6x10^-3 mol C *6.02*10^23 (1/mol) ≈3.4*10^21
C. 20.0 mol Hg*6.02*10^23 (1/mol)≈1.2*10^25
D. 0.285 mol Na*6.02*10^23 (1/mol)≈1.7*10^23
Answer:
2KClO3 -------> 2KCl + 3O2
Explanation:
First, in balancing a chemical reaction such as the one given in the question, you should understand that for an equation to be balanced, the number of atoms and ions on both sides of the equation that is the right and left side must be equal. This follows the law of conservation of mass which tells us that matter can neither be created nor destroyed but can be changed into another form.
Next is to begin balancing the equation by identifying and writing down the substances given:
KCl03 ---------> KCl + O2
Next is to count he number of the individual atoms on each side and find out if they are the same on both sides and if not you must follow the next step.
Add a corresponding number and use it to multiply the atoms involved
KClO3 ---------> KCl + O2
Oxygen is 3 on the left side and two on the other side, so we multiply the left hand side by 2 and the right hand side by 3
2KClO3 -----> KCl + 3O2
The potassium and Chlorine are no longer balanced, so you multiply the right had=nd side of KCl by 2.
2KClO3 -----> 2KCl + 3O2
The reactionis herefore balanced as both sides have equal number of atoms and ions.
Answer:
Alkali metal hydroxides can be used to test the identity of metals in certain salts. The colour of the precipitate will help identify the metal : Calcium hydroxide is soluble; no precipitate is formed.
B----------- oxide is the correct answer
Answer: Noble gas configuration is the ionisation of valence electrons using the octet rules.
Explanation:
Noble gases are the halogen, iodine etc. they form molecules using anion valence electrons in order build octet structures.