Answer:Any change that occurs without altering the chemical composition of a substance is a physical change. Physical changes can include changing the color, shape, state of matter, or volume of a substance. It is crucial to remember that physical changes never alter the chemical makeup.
Explanation:
i hope that helps u try to figure it out a little bit sorry i couldn't find your answer i didn't have much to go off of
Answer:
A) positive; added
Explanation:
Based on the reaction:
2NaHCO3(s) + 129kJ → Na2CO3(s) + H2(g) + CO2(g)
<em>2 moles of NaHCO3 requires 129kJ to produce 1 mole of Na2CO3, 1 mole of H2 and 1 mole of CO2.</em>
<em />
That means, the energy must be added being, thus, an exothermic reaction. The exothermic reactions have ΔH >0.
Thus, right answer is:
A) positive; added
Answer: Option (d) is the correct answer.
Explanation:
An equation in which electrolytes are represented in the form of ions is known as an ionic equation.
Strong electrolytes easily dissociate into their corresponding ions. Hence, they form ionic equation.
is a strong acid and 
is a strong bases, therefore, both of them will dissociate into ions.
Thus, total ionic equation will be as follows.
Elements that are usually shiny and good conductors of heat and electricity are metals.
<h3>What are conductors?</h3>
The conductors are the metal or non metal elements which allow heat and electricity to easily pass through them.
Metals are elements with good conductivity of electric current and heat. Metals have lustre characteristics. They are shiny and bendable just like copper wire, which is a metal.
Hence, elements that are usually shiny and good conductors of heat and electricity are metals.
Learn more about conductors.
brainly.com/question/18084972
#SPJ4
These are not questions but the directions or guide to completing your assignment.
I will provide you will with a choice of concept maps you can use:
- tree map
- circle maps
-comparison map ( might be best)
Please vote my answer branliest! Thanks.
