Molality= moles NaCl/ Kg H2O
250 g (1 Kg/ 1000 grams)= 0.250 Kg
Molality= 0.611 moles/ 0.250 Kg= 2.44 molal
Molar mass SiO2 = 28 + 32 = 60
<span>so moles sand = 3.4 x 10-7 / 60</span>
Answer:
Examples 1, 3 and 4
Explanation:
An unexcited atom is an atom in the ground state i.e the atom has it's valence electrons in it's lowest energy level possible. This actually implies the normal electronic configuration of the atom. Thus, examples 1, 3 and 4 have the actual electronic configuration with there valence electrons in the lowest possible energy level.
Example 1: 1S² 2S² 2P⁴
Example 3: 1S² 2S² 2P⁶ 3S¹ (There seem to be a mistake in the question provided, P energy level can only 6 electrons not 8)
Example 4: 1S² 2S² 2P⁶ 3S¹
NOTE: If you take a look at example 2, it will be deduced that the 3P energy level has only 3 valence electrons and the last valence electron jumped to 3d energy level; making that atom appear to be in it's excited state.
Answer:
It is possible to divide cells into two classifications: eukaryotic cells, which have a nucleus, and prokaryotic cells, which do not possess a nucleus but do contain a nucleoid area. In contrast to prokaryotes, which are one-celled creatures, eukaryotes may be either single-celled or multicellular in nature.
Explanation:
Hope it helps:)
The theoretical yield of copper is a 78:32 ratio.