Proton; neutron
Protons have a positive charge
Neutrons are neutral
Electrons have a negative charge :)
Answer:
The four elements are most likely halogens which belong to group 7A in the periodic table.
Explanation:
The elements most likely are halogens because they usually display the same pattern of bonding as they are all diatomic molecules that need one electron to fill their outermost shell.
Another thing is that, halogens possess very strong type of ionic bonds which make them very reactive such that they react with metals to form salts. Due to this reason, they are called salt dormers.
There are other properties of these elements too such as: atomic radius, melting and boiling points, electronegativity e.t.c. They may increase or decrease down the group.
The elements belong to group 7A.
Heat given out to the surroundings by the system = 225 J
Work done by the system on the surroundings = 645 J
According to the energy conservation, the energy can neither be created nor it can be destroyed, it can transform from one form to another. Hence, the energy which is lost to the surrounding as a work done and heat came from the internal energy of the system.
Hence, the change in the internal energy = - 225 - 645 = - 870 Joules
Negative sign means that the internal energy of the system is decreased by 870 Joules
When you walk your foot pushes down on the ground while the ground pushes back on your foot.
answer:
the reason is to ensure more solute is dissolving as it cools down. it is important to do it slowly because water will be sucked into buchner flask by a partial vaccum through the rubber tubing and be able to arrange molecules.
