Answer:
the newspaper one is a chemical change because the chemicals in the paper have reacted with something and turned a different color. the wax one is a physical change because it is a change in the phase of matter, which is always a physical change (still the same substance chemically)
Answer:
0.40 L
Explanation:
Calculation of the moles of
as:-
Mass = 51.24 g
Molar mass of
= 171.34 g/mol
The formula for the calculation of moles is shown below:
Thus,

Volume = 1.20 L
The expression for the molarity is:


Thus,
Considering
Given that:
So,
<u>The volume of 0.24925M stock solution added = 0.40 L
</u>
CO2 and H2O react to form H2CO3 and two bonds are broken each in CO and H2O to form H2CO3.
<h3>What is chemical bonding?</h3>
Chemical bonding refers to the forces of attraction which hold atoms of the same or different elements together in order to form stable compounds or molecules .
Chemical bonding may be either ionic or covalent.
The greater the number of bonds in a compound, the more stable the compound.
During chemical reactions, bonds are broken and new binds are formed.
There are two bonds each in CO2 and H2O.
This, in the reaction between CO2 and H2O react to form H2CO3, , the number of bonds broken in H2O is two and in CO2 is two.
Learn more about chemical bonding at: brainly.com/question/819068
Answer:
The new concentration will be 0.01 M.
Explanation:
To determine the new concentration we use the following formula.
concentration (1) × volume (1) = concentration (2) × volume (2)
concentration (1) = 0.1 M
volume (1) = 100 mL
concentration (2) = unknown
volume (2) = 100 mL + 900 mL = 1000 mL
concentration (2) = [concentration (1) × volume (1)] / volume (2)
concentration (2) = (0.1 × 100) / 1000 = 0.01 M
1. pesticides: that are sprayed on crops and flowers
2. global warming: warm winters have caused plants to shift their schedules. when the honey bees come out of hibernation, the flowers they need to feed on have already bloomed and died
3. pathogens carried by mites weaken bees