Answer:
The elements become less reactive.
Explanation:
As we move from left to right across the periodic table the number of valance electrons in an atom increase. The atomic size tend to decrease in same period of periodic table because the electrons are added with in the same shell. When the electron are added, at the same time protons are also added in the nucleus. The positive charge is going to increase and this charge is greater in effect than the charge of electrons. This effect lead to the greater nuclear attraction and reactivity increases because of greater electron affinity.
As we move down the group atomic radii increased with increase of atomic number. The addition of electron in next level cause the atomic radii to increased. The hold of nucleus on valance shell become weaker because of shielding of electrons thus size of atom increased. The electron affinity decreases because of shielding effect and thus atom become less reactive.
Answer: The object will move in the South direction.
Explanation: We are given an object of 400 N and force acting on it is 420 N from the north direction, it means the force is acting towards south.
The object will move in the direction of the net force, which is south direction.
Hence, the correct option is A.
The density of marble is between 2.6 and 2.8 grams per cm³ .
Density doesn't depend on how much mass or volume of it you have.
The density of a chip of it is the same as the density of a truckload of it.