Answer:The atom being mostly empty space. A small number of alpha particles were deflected by large angles (> 4°) as they passed through the foil. There is a concentration of positive charge in the atom. Like charges repel, so the positive alpha particles were being repelled by positive charge
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I just took the test right now to get this answer
Answer:
Rubidium
Rubidium is the first element placed in period 5.
Halogens is defined as the group of 7 periodic table. As, every periodic table contains 7 valence electrons and they only need 1 more to complete an outer shell, that is why they are extremely reactive. And according to the law that recurring patterns of the properties of elements arise when they are arranged in order of increasing atomic number. As the halogen all act very similarly with each other in chemical reaction, it is true.
3 to balance the calciums on both sides of the equation, but only if that balances the Cl on both sides of the equation to because you now have 6 Cl and 3Ca
