Answer:
O FX will be greater than FY
Explanation:
<em>Surface tension</em> can be defined as the force required to stretch one film of a given fase (usually with liquids).
This required force is proportional to the liquid's surface tension. This means that the higher the surface tension, the higher the required force to stretch it is.
Answer:
4
Explanation:
Relationship between wavenumber and Rydberg constant (R) is as follows:

Here, Z is atomic number.
R=109677 cm^-1
Wavenumber is related with wavelength as follows:
wavenumber = 1/wavelength
wavelength = 253.4 nm

Z fro Be = 4

Therefore, the principal quantum number corresponding to the given emission is 4.
Answer:
Explanation:Since the compound X has no net-dipole moment so we can ascertain that this compound is not associated with any polarity.
hence the compound must be overall non-polar. The net dipole moment of compound is zero means that the vector sum of individual dipoles are zero and hence the two individual bond dipoles associated with C-Cl bond must be oriented in the opposite directions with respect to each other.]
So we can propose that compound X must be trans alkene as only in trans compounds the individual bond dipoles cancel each other.
If one isomer of the alkene is trans then the other two isomers may be cis .
Since the two alkenes give the same molecular formula on hydrogenation which means they are quite similar and only slightly different.
The two possibility of cis structures are possible:
in the first way it is possible the one carbon has two chlorine substituents and the carbon has two hydrogens.
Or the other way could be that two chlorine atoms are present on the two carbon atoms in cis manner that is on the same side and two hydrogens are also present on the different carbon atoms in the same manner.
Kindly refer the attachments for the structure of compounds:
Atoms are made of 3 types of subatomic particles ; protons, neutrons and electrons
protons and neutrons are located inside the nucleus and electrons are found in energy shells around the nucleus. Protons are positively charged, electrons are negatively charged and neutrons are neutral. elements in their ground state are neutral with equal amounts of protons and electrons.
Atomic number is the number of protons. atomic number is characteristic for the element.
atomic number of Be is 4 therefore Be has 4 protons
answer is B. 4