Answer:
We need 2.933 L of 0.15 mg /mL of protein solution.
Explanation:
Concentration of given solution
1 mg = 0.001 g , 1 mL = 0.001 L

Molecular weight of protein = 22,000 Da =22,000 g/mol
Initial concentration in moles/liter:

Initial concentration in micromoles/mL :
1 L = 1000 mL

Initial concentration in micromoles/microLiter :
1 L = 1000,000 μL

Moles of protein required = 20 μmoles
n(Moles)=C(concentration) × V(Volume of solution)



We need 2.933 L of 0.15 mg /mL of protein solution.
Answer:
all these are physical properties except release of heat so it's probably heat energy given off
The element group which is least likely to form ions is 4A group
<u><em>explanation</em></u>
Element of group 4A has 4 valence electrons. for example Carbon which has [He] 2S2 2P2 electron configuration has 4 valence electrons.
Since 4A elements has 4 valence electrons , it means that their valence shell is half filled which is relatively stable. <em>For this reason 4A element readily form ions.</em>
Answer:
Two electrons
Explanation:
According to the octet rule, atoms must bond to each other, sharing electrons among themselves in an attempt to complete their valence shell (last layer of the electrosphere). In other words, an atom becomes stable when it has 8 electrons in its valence shell.
Oxygen atoms have six electrons in their valence shell, so to achieve the stability suggested by the octet rule (eight electrons), these atoms share two electrons, forming one oxygen gas (O₂) molecule.
Here’s what I found:
It takes very little energy to remove that outermost electron from an alkali metal. Thus, alkali metals easily lose their outermost electron to become a +1 ion. ... In fact, as you go down the 1A column, the first ionization energies get lower and lower, making cesium the most easily ionized element on the periodic table.
So basically it’s because part of what makes alkali metals so reactive is that they have one electron in their outermost electron layer.