The atomic number defines the number of protons in an atom.
Answer:
A. They must be kept separate from moisture and oxygen
Explanation:
Alkali metals refers to a group of chemical elements in the periodic table. It is the common name given to Group 1 elements (excluding hydrogen). They are generally metallic in nature with physical properties like shining lustre, silvery in appearance etc. Alkali metals include lithium, Pottasium, Sodium, Rubidium etc.
One important chemical property of alkali metals is their high reactivity i.e. they tend to react quickly with other substances. For example, alkali metals react vigorously with water to form hydroxides. They also react with oxygen to form oxides. Due to this highly reactive properties, they are kept or stored away from moisture (water) and oxygen (present in air).
Answer is 16
carbon valence = 4
oxygen valence = 6 but carbon dioxide have 2 oxygen so = 12
12 + 4 = 16
so carbon dioxide have 16 electron
Alpha helix and beta sheets are the secondary structure of protein
#1. The condition of the atmosphere at a certain time and certain place
#2. The rate of evaporation is EQUAL to the rate of condensation
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