Answer:
cell :—
•They lack a well-defined nucleus, have a nucleoid instead.
•Usually have double-stranded, circular DNA.
•Do not have mitochondria.
Eukaryotic cell :—
•Have a well-defined nucleus enclosed in the nuclear membrane.
•Have a linear double-stranded nucleus.
•Mitochondria are present.
The correct answer from the choices given is the third option. Covalent compounds have low boiling points. Also, their melting points are low. Covalent bonds have relatively low attractions which results to these properties. The bonds are easily broken by taking energy or adding energy.
Atomic mass of helium is 4.002642g/mol
(542000g)/(4.002642g/mol)*6.02*10^23 = 8.15*10^28 atoms
5.00 moles of a binary, group 2 oxide are found to have a mass of 521 g. The group 2 metal is Strontium.
According to question 5 moles of binary group 2 metal oxide mass =521 g
So, 1-mole metal oxide mass will be =521 / 5=104.2 g
Now, as metal oxide is group 2 oxide so metal: oxygen =1: 1
So the mass of metal is =104.2-16=88.2 gm (as the atomic mass of oxygen is 16 g
Therefore, the metal is Strontium(Sr) whose atomic mass is 87.62 g which is nearly 88.2 gm
So, the formula of metal oxide is SrO
The group two metal here is Sr which is strontium and lies in the same group as calcium.
To learn more about group 2 metals, visit:
brainly.com/question/18328178
#SPJ9