Answer:
density of a piece of metal = 7 gr/ml
Explanation:
See the file please
Answer:
a. Pb 208
b. About 21.7 minutes
c. only a trace amount
Explanation:
It under goes beta decay.
There should be virtually nothing after an hour
Answer:
NH3 is polar due to the bonds between nitrogen and hydrogen which have different electronegativity and due also to its asymmetrical shape.
Explanation:
NH3 is polar as there are 3 dipoles in the ammonia molecule that do not balance each other out.
Considering the N-H bond which is polar because N with an electronegativy of 3.0, is more electronegative than H, with an electronegativity of 2.1. The is overall asymmetrical shape of NH3
means that the dipoles remains unbalanced and do cancel out each other making the NH3 polar.
Three of the functions of proteins are as antibodies, as enzymes and as messengers. As antibodies, they protect the cells from diseases ie they fight diseases. As enzymes, they regulate the chemical reactions within cells, and thirdly they transmit signals as messengers such as hormones do in co-ordinating biological processes. Proteins are so diverse because of their unique 3-D structures which their polymers form from the 20 amino acids available as their building blocks.
Helium is a light gas. Movement can be predicted by which chamber has the lighter gas(es) and which chamber has the heavier. constant changes can also be a variable. If the gas is constant, then changes are more easily predicted.
