Answer:
d. 4.
Explanation:
Hello,
In this case, the required number on milligrams is:
It means that it has four significant figures which are counted for 7, 5, 0 and 2, considering that zero as it is to the right of first nonzero digit (7).
Regards.
The answer should be compound
Through the process of conduction, heat van be trnafered between two solids.
Answer:
See Explanation
Explanation:
Pb2O3 is better formulated as PbO.PbO2. It is actually a mixture of the two oxides of lead, lead II oxide and lead IV oxide.
This implies that this compound Pb2O3 (sometimes called lead sesquioxide) is a mixture of the oxides of lead in its two known oxidation states +II and +IV.
Hence Pb2O3 contains PbO and PbO2 units.
Answer:
The respective figure with label and targets is missing but yet the definitions and stability considerations can help you, so I explain them below.
Explanation:
Remember these definitions:
- Atomic number = number of protons
- Mass number = number of protons + number of neutrons
Hence,
- When one proton is added, both atomic number and mass number increase by one.
- When one neutron is added, atomic number remains the same, but mass number increase.
The neutrons provide stability to the nucleus of the atom by compensating the electrostatic repulsion force that arise from the fact that positive charges are forced to be so close in the nucleus.
Since the more protons are added to the nucleus the stronger the repulsive force inside the nucleus are, as the atomic number increase the neutron number must increase too.
For the ligther elements (lower atomic and mass numbers) the ratio of neutrons to protons is very close to 1.
For heavier elements (greater atomic and mass numbers) the ratio of neutrons to protons increase: proportionally more neutrons are needed to provide stability to the nucleus.