A: Chemistry = Chemical Changes 1.4 Solutions and Concentrations Flashcards
What is a solution?
A solute dissolved in a solvent.
What are some common examples of commercial solutions?
- Beverages
- Medicines
- Household cleaners
- Hair-care products
What can changing the ratio of solute to solvent in a solution do?
Dramatically change the properties of the solution.
What is the concentration of acetic acid in vinegar commonly used in cooking?
5% solution of acetic acid.
True or False: A concentrated solution of acetic acid is safe for consumption.
False.
Why are there regulations about the proper labeling of products?
To keep consumers safe.
Fill in the blank: The ratio of solute to solvent is often noted on the product’s _______.
label.
What are polychlorinated biphenyls (PCBs)?
PCBs are pollutants that can be present in water and fish.
Where can PCBs be found?
In water and fish living in water polluted with PCBs.
What is the maximum concentration of PCBs allowed in fish according to Canada’s health guidelines?
2 parts per million (ppm).
What is the purpose of the PCB concentration guideline in fish?
To ensure that the fish you eat will not harm you.
Fill in the blank: The maximum concentration allowed by Canada’s health guidelines regarding the level of PCBs in fish is _______.
2 parts per million (ppm).
What is the definition of concentration in a solution?
The ratio of the quantity of solute to the quantity of solution
Concentration describes how much solute is present in a given volume of solution.
What is a concentrated solution?
A solution containing a high ratio of solute to solution
Concentrated solutions have more solute compared to the volume of solvent.
What is a dilute solution?
A solution containing a low ratio of solute to solution
Dilute solutions have less solute in a given volume of solvent.
True or False: A solution with more solute than another solution of the same volume is considered more concentrated.
True
This indicates that the amount of solute is greater in comparison to the solvent.
What is the concept of concentration?
A measure of how much solute is present in a solution or mixture
Concentration is encountered in everyday situations such as buying products or assessing water quality.
Why is understanding concentration important?
It helps answer questions about solute amounts, safety limits, safety concerns, and cost-effective product purchasing
Understanding concentration aids in interpreting product information and making informed decisions.
Fill in the blank: Concentration is important for determining _______.
[solute amounts]
What types of questions can understanding concentration help you explore?
It helps explore questions about:
* Solute amounts in products
* Safe limits for chemicals
* Safety concerns with high concentrations
* Cost savings from buying concentrated solutions
These questions are relevant in both daily life and scientific contexts.
True or False: Concentration is only relevant in scientific contexts.
False
Concentration is relevant in everyday activities such as shopping and health assessments.
What are qualitative properties of solutions?
Qualitative properties of solutions are characteristics that can be observed without measuring quantities, such as colour, taste, and odour.
How can you distinguish between concentrated and dilute juice?
You can distinguish between concentrated and dilute juice by tasting, observing differences in colour, and noticing consistency.
Fill in the blank: You can get a lot of information about a substance simply by observing its _______.
physical properties
True or False: Qualitative properties require quantitative measurements to be understood.
False
List some examples of qualitative properties.
- Colour
- Taste
- Odour
What is one method to compare the concentration of two solutions?
Compare how the two different solutions conduct electricity
This involves placing two electrodes into a solution and measuring the ease of electrical current passage.
How does the concentration of a solution affect its ability to conduct electricity?
Solutions with higher concentrations are more effective at passing current than dilute solutions
Higher concentration solutions have more ions available to carry the electrical charge.
Fill in the blank: Solutions with higher concentrations are ______ than dilute solutions at passing the current.
more effective
What equipment can be used to measure the conductivity of a solution?
Two electrodes
True or False: It is always easy to tell which solution has a higher concentration by looking at it.
False
What theory explains that a chemical reaction will occur if particles collide with a certain minimum energy and orientation?
collision-reaction theory
This theory states that collisions between atoms, ions, and molecules are essential for chemical reactions.
What is required for a chemical reaction to occur according to the collision-reaction theory?
Particles must collide with a certain minimum energy and orientation
The correct energy and orientation ensure that a chemical reaction can take place.
What happens to particles after they collide in a chemical reaction?
They undergo rearrangement
This rearrangement of particles leads to the formation of new substances.
True or False: All chemical reactions involve collisions between atoms, ions, and molecules.
True
Collisions are a fundamental aspect of chemical reactions as per the collision-reaction theory.
Fill in the blank: The __________ theory states that chemical reactions involve the collision and rearrangement of particles.
collision-reaction
This theory is crucial for understanding the dynamics of chemical reactions.
What affects the speed of chemical reactions?
Concentration of solute in a solution
How does a concentrated solution compare to a dilute solution in terms of particle availability?
A concentrated solution has more particles of solute available for possible collisions
What is the relationship between the number of solute particles and the probability of collisions?
The probability of collisions increases as the number of solute particles within a system increases
Reactions with concentrated solutions occur _______ compared to dilute solutions.
more quickly
True or False: Reactions with dilute solutions occur at a faster rate than reactions with concentrated solutions.
False
What is a key reason that reactions with dilute solutions occur at a slower rate?
Collisions are less probable
What affects the speed of chemical reactions?
Concentration of solute in a solution
How does a concentrated solution compare to a dilute solution in terms of particle availability?
A concentrated solution has more particles of solute available for possible collisions
What is the relationship between the number of solute particles and the probability of collisions?
The probability of collisions increases as the number of solute particles within a system increases
Reactions with concentrated solutions occur _______ compared to dilute solutions.
more quickly
True or False: Reactions with dilute solutions occur at a faster rate than reactions with concentrated solutions.
False
What is a key reason that reactions with dilute solutions occur at a slower rate?
Collisions are less probable
