Answer:
Hello!!! Princess Sakura here ^^
Explanation:
The precipitate forms when one of the compounds is insoluble. In double replacement reactions, the positive ions and the negative ions are dissolved reactants that switch places to form the precipitation reaction.
Answer:
These continents were joined together at one time in the past.
Explanation:
Identical rock types, identical fossils, and very similar mountain ranges are found on different continents that are separated by a wide ocean. Which of these BEST explains these observations?
I'm not suree.. is his science?
Answer:
Four covalent bonds.
Explanation:
Hello,
In this case, given the attached picture in which you can find the Lewis dot structure for metanal (formaldehyde) we can see two C-H bonds and two C-O bonds via a double bond, thus, we can compute the type of each bond given the electronegativities of hydrogen, carbon and oxygen which are 2.1, 2.5 and 3.5 respectively:

Thus, since both electronegativity difference are less 1.7 we infer that all of them are covalent, therefore, it has four covalent bonds, two C-H bonds and a double C-O bond.
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C becuase that is the one that you would have to do becuase that is the only option