The correct answer is elements in family 7 have similar properties because elements in the same group or family have the same number of valence electrons.
Answer:
Fossils, the shape of continents, the mid-ocean ridge system, sea floor sediment deposits, and the magnetism of rocks.
Explanation:
Fossils, the continent's shape, the mid-ocean ridge system, sea floor sediment deposits, and the magnetism of rocks on the sea floor are the evidences that support the theory of plate tectonics in the area. Fossils provides information to us when and where plants and animals once existed. Due to diverging plates, some life became isolated, and evolved into new species. Continental ‘fit’ through coastline matching. Some division of continents look as though they should fit together, e.g. South America and Africa.
Answer:
It is greater than -600kJ/mol and the amount of energy required to break bonds is greater than the amount of energy released in forming bonds.
Explanation:
In an endothermic reaction, the reaction requires a determined amount of energy to occurs.
The reaction of the problem has H = -600kJ/mol. The reaction is endothermic and the energy that the reaction needs is absorbed by the reactants. That means, the energy of products:
Is greater than -600kJ/mol and the amount of energy required to break bonds is greater than the amount of energy released in forming bonds.
Answer:
A lithium atom has 3 protons and 3 electrons. It can lose one of its electrons, making it an ion. It now has more positive protons than electrons so it has an overall positive charge. Therefore it is a positive ion.
Explanation:
Lithium, an alkali metal with three electrons, is also an exception to the octet rule. Lithium tends to lose one electron to take on the electron configuration of the nearest noble gas, helium, leaving it with two valence electrons.
