The atomic theory started with Democritus, who stated that all space was made up of indivisible particles called atoms, though Aristotles refuted that statement by saying that matter didn’t exist, he believed in the four elements: air, fire, water, and earth. Then came Dalton, who revived Democritus’s ideas and proposed the law of multiple proportions, he revived the idea that all space was made of atoms. Soon after, J.J Thompson discovered the electron by using cathode rays. Max Planck developed the quantum theory by stating that electromagnetic radiation could only be emitted in quantized form (later called quanta). Einstein furthered this idea with studies of light. Robert Millikan eventually measured the charge of a single electron. Ernest Rutherford used a gold foil experiment and discovered the nuclei, considering his alpha particles were deflected by some object. Niels Bohr made the atomic model with electrons spinning around an atom’s nucleus, Erwin Schrodinger describes how electrons have wave like properties. James Chadwick then discovers the neutron!
There ya have it!
Answer:
A = 349 g.
Explanation:
Hello there!
In this case, since the radioactive decay kinetic model is based on the first-order kinetics whose integrated rate law is:

We can firstly calculate the rate constant given the half-life as shown below:

Therefore, we can next plug in the rate constant, elapsed time and initial mass of the radioactive to obtain:

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Group 7a would have an ion charge of -1 because it has 7 valence electrons and it wants to gain one more electron(which is negative) to have a full shell of 8
<span>UV gel enhancements rely on ingredients from the monomer liquid and polymer powder chemical family. The chemicals from the polymer powder family </span><span>can absorb and retain extremely large amounts of a liquid relative to their own mass. Water-absorbing polymers, </span>can absorb aqueous solutions through hydrogen bonding with water molecules.
Answer:
A flame test could help by seeing what things it could catch on fire from or the things that could happen with acids etc. I would test the medicine by asking someone who has had it in their life, asking doctors or I would maybe use it myself maybe. (I don’t know about c, sooo sorry)