Answer:
A
Explanation:
Protons are positive
Neutrons are neutral
Electrons are negative
Protons and Neutrons are in the nucleus
Electrons are orbiting around the nucleus
Answer:
Option (2), (3) and (5).
Explanation:
Chemical change: It is a chemical reaction in which arrangement of atoms of one or more than one substance changes to give new substances as a product.Chemical change can be in form of : color change, formation of precipitate, formation of bubbles.
In option (2), bubbles were produced when iron was placed in acid which means gas was released on adding iron to acid.Yes, it is a chemical change.
In option (3), solid that is precipitate is obtained as a product from the reaction between two liquids which means that change in arrangement of atom had taken place.Hence, a chemical change.
In option (5), white substance turned blue when water was added. Color of white solid changes to blue which means that chemical change has taken place.
So, option are (2), (3) and (5) are examples of chemical changes.
Answer: a full s and a full p sublevel
Explanation: "noble gases. They are an especially important group of the periodic table because they are almost completely unreactive, due to their completely filled outermost s and p sublevels."
Answer:
for its one mole it is of 28gram. according to mole concept in one mole, there is 6.022*10^23 moles are present. so mass of 1 molecule of nitogen gas is 28/(6.022*10^23)
Answer:
Three things are required in proper combination before ignition and combustion can take place---Heat, Oxygen and Fuel.
There must be Fuel to burn.
There must be Air to supply oxygen.
There must be Heat (ignition temperature) to start and continue the combustion process.