"These" should be referring to Alkali Metals.
They include metals such as Lithium, Sodium, Potassium etc.
They're classified as Group I elements because they all have one outmost shell electrons. This is why these metals are so reactive because they only need to lose one electron in order to achieve the octet of electrons (or duplet for Lithium), which means complete outmost shell electrons (2 or the 1st shell, others are 8).
The reason why they're especially reactive to Halogens (Group VII) elements are that Halogens have 7 outmost shell electrons, which only needs one more electron in order to get to the octet of electrons. So, if an Alkali metal reacts with a Halogen, the metal would give one of their electrons to the Halogen, that way, both of the elements can have an octet of electrons (or duplet).
Answer: the weight of a object
Explanation:
Answer:
anther: produces pollen
ovule: contains egg cells
sepal: protects the flower bud
petal: surrounds the reproductive structures
Explanation:
Most fungi is spread throughout the world by
A. Animals ??
Answer;
- radiometric dating of rocks
- fossil evidence
- gradual processes of rock
Explanation;
Radiometric dating confirms that Earth is ancient and explains how extremely slow processes can result in major changes to Earth’s surface. Evidence from radiometric dating indicates that Earth is about 4.54 billion years old. The geology or deep time of Earth's past has been organized into various units according to events which took place.
-The ages of Earth, Moon, and meteorites, radiometric dating has been used to determine ages of fossils, including early man, timing of glaciations, ages of mineral deposits, recurrence rates of earthquakes and volcanic eruptions, the history of reversals of Earth's magnetic field, and the age and duration of a wide variety of other geological events and processes.
