It’s fluorine it has a big jump from the 6th to 7th ionisation energy.
It’s electronic configuration is 1s2 2s2 2p5 as it has 9 electrons and 7 electrons in outermost shell.
Therefore it’s in group 7, as after the 7 electrons are removed, the 8th electron is removed from a quantum shell closer to the nucleus.
This results in greater ionisation energy due to stronger electrostatic forces of attraction between positively charge nuclei and electrons ( + shorter distance)
Answer:
Mixtures can be either homogeneous or heterogeneous. A mixture in which its constituents are distributed uniformly is called homogeneous mixture, such as salt in water. A mixture in which its constituents are not distributed uniformly is called heterogeneous mixture, such as sand in water.
Explanation:
Calories heat added = Mass of glass times temp. increase times specific heat of glass
calories (small calories) = l.0 g x 20 degrees x .16 calories/gm/degree C = 3.2 calories
Answer:

Explanation:
Regardless of the type of gas, 1 mole at standard temperature and pressure (STP) occupies a volume of 22.4 liters. In this case the gas is helium (He).
We can set up a ratio.

Multiply by the given number of moles.

The moles of helium will cancel.


Multiply.

5.25 moles of helium gas at STP is 117.6 liters of helium.
Answer:
The molecule has a bent geometry
Explanation:
Let us look again at the principles of VSEPR theory. The shape of a molecule depends on the number of electron pairs that surround the valence shell of the central atom in the molecule.
Lone pairs distort the molecular geometry away from what is expected on the basis of VSEPR theory.
The molecule described in the question has the form AEX2. Two substituents and one lone pair form three electron domains around the central atom. The expected geometry is trigonal planar but the observed molecular geometry is bent because of the lone pairs present.