Answer:
We know that,
Density= mass upon volume.
mass= 21.93g
Volume= 49.3 - 46.3
= 3 cm³
Density = 21.93÷ 3
= 7.31 g/cm³
Hope it helps :))
A for number 1 and C for number 2 im sorry i dont know the rest. :3
If you count the number of electrons (small dots), you have the atomic number. In this case you have 11 so this atom is a sodium atom. Sodium has 1 valence electron (electron on the outer shell) and chlorine has 7. This means that if sodium gave one electron away and chlorine would obtain one electron, they would both have the (ideal) noble gas conformation (full outer shell).
Explanation:
A physical change is change that alters the physical properties of matter especially its form and state.
In many cases, the change is easily reversible.
Examples are change of state such as boiling, melting, freezing, condensation, sublimation e.t.c
A chemical change is one in which a new kind of matter is formed. It is always accompanied by energy changes.
Examples are combustion, rusting , precipitation, milk souring.
- Chemical changes are irreversible
- Physical changes do not lead to the formation of new kinds of matter.
- Most physical changes requires little energy.
You can use this knowledge to solve your problem
learn more:
Chemical change brainly.com/question/9388643
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Answer:
Explanation:
19) it is 3d10 instead of 4d10
20) it is missing 3p6, and 4s2 before 3d5
21) Ra is not a noble gas
22) Cs is not a noble gas
