Answer:The sun
Explanation:
Coal and crude oil are made from the remains of plants and animals that died long ago. The primary energy source in an ecosystem is the sun. Plants take in energy from the sun to produce high energy molecules which are transferred along the food chain to animals. When these plants and animals die, the high energy molecules are now stored in fossil fuels. Recall that the molecules were formed using energy from the sun, therefore, the sun is the energy source from which the high energy molecules contained in fossil fuels are obtained.
Answer:
boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te), polonium (Po) and astatine (At)
Explanation:
metalloids are elements that are in between the metals and nonmetals. they are in between because they have properties of both metals and nonmetals.
you can search "metalloids on the periodic table" and go to images to see what i mean :)
Answer:
A) It shows how electrons are distributed in the Shells of an Iron atom.
Explanation: Took the test on Edge
Answer:
The reason they don't react is because Elements with full octets are stable, the Elements with no unpaired electrons do not react at all in the decay.
Answer:

Explanation:
In this question, we wish to find the missing nuclei for the equation:

In order to find the missing species, we need to use the charge and mass balance law. That is, the mass should be conserved: the total mass on the left-hand side with respect to the arrow should be equal to the total mass on the right-hand side with respect to the arrow:

Notice from here that:

So far we know that the mass of X is 4. Similarly, we apply the law of charge conservation. The total charge should be conserved:

From here:

We have a particle:

Looking at the periodic table, an atom with Z = 2 corresponds to helium. This can also be written as an alpha particle:
