The answer is the last one .... The ability to do work and cause change
Answer: polar molecule.
Explanation:
The boiling point is the temperature at which the vapor pressure of a liquid equals the external pressure surrounding the liquid. The boiling point is dependent on the type of forces present.
Iodine monochloride (ICl) is a polar molecule due to the difference in electronegativities of iodine and chlorine. Thus the molecules are bonded by strong dipole dipole forces. Thus a higher temperature is needed to generate enough vapor pressure.
Bromine
is a non polar molecule as there is no electronegativity difference between two bromine atoms. The molecules are bonded by weak vanderwaal forces and thus has low boiling point.
Answer:
The first element in the periodic table is hydrogen.
Explanation:
Hydrogen has an atomic number of one, making it the first element of the periodic table. The atomic number of an element is just the number of protons in the nucleus, so hydrogen has one proton. The neutrons and electrons do not affect the atomic number. After hydrogen with one proton comes helium with two, lithium with three, beryllium with four, and so on.
<u>Plum Pudding Model(Thomson's atomic model)</u>
- Thomson's atomic model states that an atom has a positive sphere charge with electrons embedded inside it. He compared the atom with a plum pudding,as the electrons according to him seemed like the dry fruits embedded in the spherical pudding.
<u>Rutherford's Model</u>
- However Rutherford bombarded high energy streams of α-particles on a thin gold foil of 100 nm thickness. The deflection produced by the trajectory of these high energy α-particles after interaction with the thin sheet of gold was studied by placing a screen made up of zinc sulfide around the gold foil.
- The major observations made by Rutherford were that a very huge fraction of α-particles passed through the gold sheet without getting deflected. Thus he concluded that the major part of an atom must be empty.
- Very few α-particles got deflected minutely or at very small angles by the gold sheet when they were bombarded against it. Also very few particles got deflected at large angles. This made him conclude that the positive charge is concentrated in a very small region and is not distributed uniformly.
From the above observations he gave the following postulates:
- An atom is made up of positively charged particles. The mass of an atom was concentrated in small region which is named as the nucleus of an atom.
- The nucleus is surrounded by electrons which are negatively charged particles which revolve around the nucleus in a fixed circular path called as “orbits.”
- An atom is electrically neutral because electrons are negatively charged and the nucleus is positively charged. The electrons are held by the nucleus due to a strong electrostatic force.
- Compared to the total size of an atom the size of the nucleus is very small.