Explanation:
Two acids we come into contact with in an average week
- Vinegar is an 10% solution of acetic acid
in water. Used in salad dressing and while cooking food. It has a sour taste. - Citric acid present in fruits and vegetables like : lemons, orange, tomatoes etc. It is a weak organic acid with sour taste.
Two bases we come into contact with in an average week.
- Baking soda (
) is used in baking food like: cakes, cookies, breads. Baking soda is one of the ingredient while baking breads and cakes. - Caustic soda (NaOH) is used for preparation of detergents, papers , soaps etc. We use soaps and detergents for washing.
Electronegativity of an element decreases as we move down a group on the periodic table and electronegativity increases while moving from left to right across a period on the periodic table.
Explanation:
- The electronegativity increases as we move from left to right across a period because from left to right across a period, the nuclear charge is increasing Hence the attraction for the valence electrons also increases.
- As we move down a group, the atoms of each element have an increasing number of energy levels. The distance between the nucleus and valence electron shell increases and reduces the attraction for valence electrons. Hence electronegativity decreases as we move from top to bottom down a group.
Answer:
1s < 2s < 2p < 3s < 3p < 4s < 3d < 4p < 5s
Explanation:
You can predict the order of orbital energies by constructing a diagram as shown below.
Follow the arrows to get the orbitals in order of increasing energy.
The order is
1s < 2s < 2p < 3s < 3p < 4s < 3d < 4p < 5s
Freezing something makes it solid and melting something makes it a liquid
