Which statement is true according to modern atomic theory? Choose the correct answer. Cathode rays are composed of protons.
Atoms can never combine with any other atoms.
Atoms may be divided in ordinary chemical reactions.
Atoms of the same element may have different mass numbers.

Find the number of grams of hcl needed to react completely with .50 moles of magnesium.

For each of the following compounds, decide whether the compound's solubility in aqueous solution changes with ph. if the solubility does change, pick the ph at which you'd expect the highest solubility. you'll find ksp data in the aleks data tab. compounds does solubility change with ph

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