Answer:
C.AgNO3 + NaCl → AgCl + NaNO3
Explanation:
Vapor pressure is a criteria for a substance's volatility. This is the ability of a substance to transition from liquid to vapor. When the vapor pressure equals the external pressure, liquid turns to gas. Hence, if the substance has higher vapor pressure, then it is volatile. <em>Therefore, Sample A is more volatile than Sample B.</em>
Number of moles = 0.0688 moles of NaoH
volume = 0.250 L
Molarity = moles of solute / volume ( L )
M = 0.0688 / 0.250
M = 0.28 M
Answer B
Answer:
b). silver (Ag)
Explanation:
If you look at the periodic table, you just need to look at the atomic number of the element, because the atomic number tells you how many protons there are in the nucleus of the element.
But do be careful because some periodic tables have the molar mass at the top left corner, but the one I use has the atomic number at the top left corner, so make sure you look for the atomic number and not the molar mass.
Answer:
Atom is the building block of matter. The atom itself made up of subatomic particles electron, proton and neutron.
Explanation:
Long time ago, Greek philosopher thoughts that matter can be divided into smaller particles until a point is reached when the basic unit is obtained which can not be further sub divided. A Greek philosopher Democritus called these basic units "Atom".
Later on modern research showed that atom could be divided into smaller particles electron, proton and neutron. These smaller particles are called sub-atomic particles of atom.
Atoms are the fundamental unit of matter. Every thing in the universe that occupy space and have mass is called matter. we can say that every matter is composed of atoms. while the atom is composed of subatomic particles called electron proton and neutron.
Electron:
The electron is subatomic particle that revolve around outside the nucleus and has negligible mass. It has a negative charge.
Symbol = e-
Mass= 9.10938356×10-31 Kg
It was discovered by j. j. Thomson in 1897 during the study of cathode ray properties.
Proton and Neutron:
An atom consist of positively charged central core (nucleus) that is made up of Proton and neutron. Proton has positive charge while neutron is electrically neutral. Proton is discovered by Rutherford while neutron is discovered by James Chadwick in 1932.
Symbol of proton= P+
Symbol of neutron= n0
Mass of proton=1.672623×10-27 Kg
Mass of neutron=1.674929×10-27 Kg
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other. For example if neutral atom has 6 protons than it must have 6 electrons.
