There is no element with one valence electron and six energy levels. Only two valence electrons and six energy levels.
Answer:
Calcium
Explanation:
A: Calcium is a group 2 element with two valence electrons. Therefore, it is very reactive and gives up electrons in chemical reactions. It is likely to react with an element with six valence electrons that “wants” to gain two electrons. This would be an element in group 6, such as oxygen.
Answer:
A Wave the fumes from the test tube toward the nose with a hand and inhale
Explanation:
The correct answer is: sea stars
All animals listed above are invertebrates. One of the characteristic of invertebrates are that they are protostomes with the exception of Echinodermata (sea stars). The difference between protostomes and deuterostomes is in their embryonic development (orgin of mouth and anus).
In protostomes the mouth forms first: the oral end of the animal develops from the first developmental opening. On the other hand in deuterostomes the first opening (the blastopore) becomes the anus, and the oral end of the develops from the second opening.
Humans are also deuterostomes.
The greatest threats to coral reefs is the rising temperature of the oceans as a result of climate change and the acidification of the oceans due to increased levels of carbon dioxide in the atmosphere which dissolves in the ocean and forms carbonic acid.Aug 3, 2015
