<u>Answer</u>:-
Name of element = Lead
Symbol ♾ of Lead = Pb
Atomic no. = 82
Atomic mass = 207.2 amu
No. of protons = 82
No. of electrons = 82
Yes, lead(Pb) is a metallic element and certainly it has 6 electron shells which means 6 energy level.
If you find anything unclear you can ask me...
Answer: The mass in 
atoms of zinc is 0.405 g.
Explanation:
Given: Atoms of zinc =
It is known that 1 mole of every substance contains 
atoms. So, the number of moles in given number of atoms is as follows.
As moles is the mass of a substance divided by its molar mass. So, mass of zinc (molar mass = 65.39 g/mol) is calculated as follows.
Thus, we can conclude that the mass in atoms of zinc is 0.405 g.
It wont melt like gold and copper would at that temperature
Answer:
3,4–diethylheptane
Explanation:
To name the compound given in the question above, the following must be obtained:
1. Determine the functional group of the compound.
2. Determine the longest continuous carbon chain. This gives the parent name of the compound.
3. Identify the substituent groups attached to the compound.
4. Give the substituent groups the lowest possible count by naming them alphabetically.
5. Combine the above to obtain the name of the compound.
Now, we shall name the compound given in the question above as follow:
1. The compound belongs to the alkane family since it has only single bonds.
2. The longest continuous carbon chain is 7 i.e the parent name of the compound is heptane.
3. The substituent group attached to the compound is ethyl (–CH2CH3). There are two ethyl groups attached to the compound.
4. The two ethyl group is at carbon 3 and 4 (i.e number from the right to the upper branch chain).
5. The name of the compound is:
3,4–diethylheptane.
0,15 moles of NaOH-------in------------1000ml
x moles of NaOH------------in--------100ml
x = 0,015 moles of NaOH
final volume = 150ml
0,015 moles of NaOH---in-------150ml
x moles of NaOH--------------in-----1000ml
x = 0,1 moles of NaOH
answer: 0,1mol/dm³ (molarity)
