Answer:
They are held together by hydrogen bonds
Explanation:
Hydrogen bonds are special dipole-dipole attractions between polar molecules in which a hydrogen atom is directly joined to a highly electronegative atom(oxygen or nitorgen or fluorine).
Such molecules includes water, alkanoic acids, ammonia and amines.
A hydrogen nucleus has a high concentration of positive charge. The bond is actually an electrostatic attraction between the hydrogen atom of one molecule and the electronegative atom(O or N or F).
Hydrogen bonds are very effective in binding molecules into larger units. Most substances that joins with hydrogen bonds have a higher boiling point and lower volatility.
This is why we have a strong intermolecular bond between water molecules.
It is important to take note of th temperature in determining the density of a substance because this will set as a basis and will likely be a variable in the experiment because this will also contribute on the effects of the experiment and a basis of how the experiment has turned to be that way.
Answer:
30 neutrons
Explanation:
Since the mass of the iron nuclide is 56 , there must be 56−26=30 neutrons, 30 massive, neutral particles in this iron nucleus.
Answer:
The square root of the molar mass of B ÷ the square root of the molar mass of A
Explanation:
Graham’s Law applies to the effusion of gases:
The rate of effusion (r) of a gas is inversely proportional to the square root of its molar mass (M).
If you have two gases A and B, the ratio of their rates of effusion is

Here is your answer

REASON:
Elements which have 4 valence electrons are generally metalloids.
The metalloids show the properties of both metals and non-metals.
We know that,
no. of protons= Atomic number
So,
Atomic no.= 32
Hence,
The element is Germanium which is a metalloid with 4 valence electrons and has 32 protons in nucleus of each atom because it has atomic no. 32
HOPE IT IS USEFUL