Answer: 43.
Explanation:
Mass number is the sum of protons and neutrons of an atom.
The number of prortons is the atomic number, so you can write:
Mass number = atomic number + number of neutrons. From which you get;
number of neutrons = mass number - atomic number = 80 - 37 = 43
All the atoms of a given element have the same number of protons. That is why the number of protons idenfies the elements and is called atomic number.
The number of neutrons of a given element may be different for different atoms of the same element.
The atoms of an element that have different number of neutrons are called isotopes. So, different isotopes of the same element have same atomic number but different mass number.
Answer:

Explanation:
When heat is supplied to a substance, the temperature of the substance increases according to:

where
Q is the amount of heat supplied
m is the mass of the substance
C is the specific heat capacity of the substance
is the initial temperature
is the final temperature
For the sample of magnesium in this problem, we have:
m = 63 g is the mass
Q = 6689 J is the hear supplied
C = 1.023 J/gC is the specific heat capacity
is the final temperature
Solving the formula for
, we find the final temperature:

Answer:
Man-made resources
Explanation:
Humanized resources are items or substances that have value to human lives that do not occur in the natural world. Examples of man-made resources include plastic, paper, soda, sheet metal, rubber and brass. These contrast with natural resources, such as water, crops, sunlight, crude oil, wood and gold.
Answer. Answer: Scientists study how things work, while engineers create new things
Answer:
Making models
Explanation:
Classifying is the grouping together of items that are alike in some way. Answer: Making models involves creating rep- resentations of complex objects or processes.