Answer:
MgO has a highest melting point
C5Br has lowesst
Explanation:
It takes a lot of energy to overcome the strong electrostatic forces of attraction between oppositely charged ions, so ionic compounds have high melting and boiling points. ... Magnesium oxide is made from ions with two charges (Mg 2+ and O 2-) and so has a much higher melting point of 2852°C.
630g
Explanation:
firstly the equation has to be balanced. 2H2+o2>2H2o.
finding the mole of hydrogen?
mole = 70/2 which is equal to 35 mole of hydrogen.
35 mole of hydrogen is equal to the mole of water.
finding the mass of water=?
35=mass/18
mass= 35*18=630g of water
Answer:
transmission EM (TEM) and the scanning EM (SEM)
Explanation:
Electron microscopy (EM) is a technique for obtaining high resolution images of biological and non-biological samples. It is used in biomedical research to examine the detailed structure of tissues, cells, organs and gross cell bodies.
There are two main type of electron microscope
- the transmission EM (TEM)
- the scanning EM (SEM)
- Transmission electron microscopes are used to see thin specimens so that electrons can produce a projection image. TEM can be adapted in many ways to conventional (compound) light microscopes.
- TEM is used for the internalization of cells , the formation of protein molecules, viruses, and organization of molecules in the cytoskeletal filaments. And arrangement of protein molecules in cell membranes.
The advantage of using an orbital notation is that it shows the electron distribution in shells.
<span>Dot structures only show the valence electrons of an atom which are the electrons found at the outermost shell. The orbital notation gives a more detailed depiction of the electrons in each shell. This is most advantageous for atoms that have special cases. </span>
<span>Some examples of atoms that have special electronic configurations are copper and chromium. For example, copper is more stable when the 3d subshell is completely filled. This leaves the 4s subshell with only 1 electron. Chromium is also more stable when its s and d subshells are only half full. The orbital notation depicts these special cases, whereas the dot structure does not.</span>
Answer : The value of 'R' is 
Solution : Given,
At STP conditions,
Pressure = 1 atm
Temperature = 273 K
Number of moles = 1 mole
Volume = 22.4 L
Formula used : 
where,
R = Gas constant
P = pressure of gas
T = temperature of gas
V = volume of gas
n = number of moles of gas
Now put all the given values in this formula, we get the values of 'R'.
Therefore, the value of 'R' is .
