Answer:
A- beryllium
B- calcium
C- magnesium
Explanation
NOTE: all element in group 2 have 2 balance electrons
First let’s start with B- number of electrons= number of protons which is equal to the atomic number. therefore, the answer is calcium as it’s atomic number is 20
C- magnesium will have three energy levels considering it has 12 electrons (2,8,2).
A- beryllium is the lightest one in group 2 as it has the atomic mass of 9.0122.
Each atom of bromine has 35 protons and this is bromine's atomic number. <span />
B. 1, 2, 1, 2. You balance the equation by making sure there are equal elements on both sides.
Answer:
Na+
Explanation:
The equation would be:
HCl (aq) + NaOH (aq) --> HOH (l) + NaCl (aq)
The equation is already balanced and the NaCl will disassociate in Na+ and Cl- and HCl will disassociate into H+ and Cl- and NaOH will disassociate into Na+ and OH-. Na+ is on both sides of the equation and stays the same, so Na+ will be the spectator ion.
Explanation:
Kinetic energy is defined as the energy obtained by an object due to its motion. Whereas energy obtained by an object due to its position is known as potential energy.
(a) When a sled is resting at the top of a hill then it means the sled in not moving. Hence, then it has only potential energy. But when a sled sliding down the hill then it is moving from its initial position.
Hence, when a sled is sliding down the hill then it has higher kinetic energy.
(b) When water is above the dam then it only has potential energy but when the water falls over the dam then it has higher kinetic energy.