Orbital s is always the first one to fill up
Bases feel slippery and for number 7 the type of solution is acidic :)
A conclusion is basically something over all you wrote. So basically what you can do for a conclusion is maybe write something about each paragraph(s) but make it short sorry if this is bad :(
<span>Dalton's atomic theory proposed that all matter was composed of atoms, indivisible and indestructible building blocks. While all atoms of an element were identical, different elements had atoms of differing size and mass. Dalton also stated that all compounds were composed of combinations of these atoms in defined ratios. He postulated that chemical reactions resulted in the rearrangement of the reacting atom.
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The answer would be D. Soluble means that it can be dissolved by water.