Answer:
<em>The correct option is B) two liquids are mixed at room temperature and a gas forms.</em>
Explanation:
A chemical change can be described as a change which results in the formation of a new substance by the reactants. In the option B, two liquids react to form a new product which is a gas. Hence, it is an example of chemical change.
Other options,like option D, is not a chemical change as by crushing a solid no new product is formed. Option C is also not correct because as when salt dissolves in water, no new product is made.
Answer:
e. When the indicator changes color and remains, 2 more drops of the solution in the buret should be added.
Explanation:
<em>Which statement is incorrect?
</em>
<em>Select one:
</em>
<em>
a. The volume of solution in the buret should be recorded when the endpoint is reached.
</em> CORRECT. At the endpoint, the titrant is expected to have completely reacted with the titrand.
<em>b. It is good practice to place the flask over a white background to better observe the color change of the solution.</em> CORRECT. Using a white background makes it easier to detect the changes in the color of the indicator.
<em>c. The endpoint is when the indicator changes color.</em>
CORRECT. This is the function of an indicator.
<em>d. Phenolphthalein will go from a colorless solution to a pink solution for the addition of NaOH to an acid solution.</em> CORRECT. Phenolphthalein is colorless when pH < 8.3 and it is pink when pH > 10.0.
<em>e. When the indicator changes color and remains, 2 more drops of the solution in the buret should be added.</em> INCORRECT. When the endpoint is reached, no more titrant should be added.
Answer:
Water (H2O) is polar because of the bent shape of the molecule. The shape means most of the negative charge from the oxygen on side of the molecule and the positive charge of the hydrogen atoms is on the other side of the molecule. When solutes are added to water, they may be affected by the charge distribution
Explanation: