Atoms have positive charges? or nuclei? Rutherford conducted the infamous gold foil experiment from which he concluded an atom mist contain a dense positively charged part with a orbiting shell of negative parts. That model was refined many times to form the current model of the atom.
Usually when metals and Nonmetals join they are held together by ionic bonds.
1<span>Pepsi is a heterogeneous mixture Oatmeal with raisins is a homogeneous mixture.
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<span>Milk is a pure substance, not a mixture
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