D)By increasing or decreasing the size of systems that are difficult to study we make it easier for students to see how they work and therefore make it easier for them to learn.
Explanation:
Scientific models makes it easier to teach students about systems because their sizes can be adjusted and this makes it easier for students to see how they work.
A model is a simplification of the real work. It takes a part of the real world and studies it.
Models are highly desired in teaching and understanding very complex systems.
- Since a tutor owns the control of the model, they can make adjustments on them to a scale that is convenient to work with.
- Also, a part of a system can be studied one at a time making it simple for students to comprehend.
learn more:
Models brainly.com/question/1858613
#learnwithBrainly
Answer: A
Explanation: Beta particles have a charge of -1
Moles = mass/molar mass
moles = 2.3
molar mass = 278
=> mass = moles*molar mass = 639.4g
When sulfur reacts with zinc metal is forms a compound known as zinc sulfide.
<h3>
Name of the elements</h3>
The names of the elements that make up the compound will be determined from the atomic mass of the elements.
<h3>Which element has atomic number 30</h3>
The element that atomic number of 30 is zinc and it has oxidation number of +2.
<h3>Which element has atomic number 16</h3>
The element that atomic number of 16 is sulfur and it has oxidation number of -2.
<h3>Chemical reaction between sulfur and zinc metal</h3>
Zn²⁺ + S²⁻ --------> ZnS
Thus, when sulfur reacts with zinc metal is forms a compound known as zinc sulfide.
Learn more about zinc sulfide here: brainly.com/question/20806552
#SPJ1
Avogadro's number is defined as the number of elementary particles (molecules, atoms, compounds, etc.) per mole of a substance. It is equal to 6.022×1023 mol-1 and is expressed as the symbol NA.