The answer is (3) neutrons and protons. The nucleus of an atom is composed of neutrons and protons. There is only one atom nucleus composed of only protons, Hydrogen. And the electrons are moving in high speed around the nucleus.
Answer:
B. what happens when iron rusts in the presence of water
Explanation:
Chemistry is a branch of science involving the composition and changes of matter. In other words, a chemist, who is a trained specialist in the science of chemistry, seeks to answer questions related to properties of matter.
In this question, a chemist is most likely to study "what happens when iron rusts in the presence of water" because it involves a change in the chemical properties of a substance (iron) i.e. a chemical change. However, what happens when ice melts to liquid water is a physical change.
Answer:
pancreatic amylase, lingual amylase, intestinal amylase
Explanation:
When considering a sugar drink, the enzymes involved in its digestion are first the alpha amylase found in saliva, responsible for degrading starch molecules, thus generating unique molecules of monosaccharides. Then the ones in charge of continuing with the digestion will be the pancreatic amylase and the intestine at the duodenal level.
Given :
a. 
b. 
c. 
d. 
.
To Find :
Find the most likely vale of x for each one .
Solution :
a .
Because boron have valency of 3 .
So , x = 3 .
b .
Valency of carbon is 4 .
x = 4 .
c .
Valency of nitrogen is 3 .
Therefore , x = 3 .
d .
Now ,we know valency of carbon is 4 and hydrogen is 1 .
Also , two hydrogen are already there .
So , only 2 electrons left to share .
Since , chlorine have valency of 1 .
Therefore , only 2 electrons of chlorine can connect .
x = 2 .
Hence , this is the required solution .
Answer:
Potential energy = 441 N
Explanation:
Given:
Mass M = 15 kg
Height = 3 m
Find:
Potential energy
Computation:
Potential energy = mgh
Potential energy = (15)(9.8)(3)
Potential energy = 441 N
