Answer:
2
Explanation:
The atom shown in the image has 2 core electrons.
Electrons are the negatively charged particles within an atom. Therefore the total number of electrons surrounding the nucleus in the given specie is 7.
So;
We have 2 core electrons
And 5 valence electrons
The core electrons are the inner orbital electrons.
The valence electrons are the outermost electrons.
Answer:
- <u>TRUE:</u> <em>Percent concentration is one of the most common and basic concentration measurement used by general public</em>
Explanation:
In chemistry there are many <em>concentration measurements</em> used to describe the mixtures. Some of them are, percent, molarity, molality, and molar fraction, among others.
Percent concentration is a popular one because it is commonly understood and used by the non specialist people, i.e. general public.
The percent concentration of a component is defined as: (amount of component in the mixture / amount of mixture) × 100.
The amounts may be measured in mass units (e.g grams) or volume units (e.g. mililiters).
For solutions, mass percent concentration is:
- % = (mass of solute / mass of solution) × 100.
And voluem percen contration is:
- % = (volume of solute / volume of solution) × 100
Since percentage is used in many profesional and personal activities, most persons use it.
For example, rubbing alcohol, that everyone buys in pharmacies, is 70%; vinager, used in the food, is acetic acid at 5% - 8%.
Answer:
Hypothesis
Explanation:
The following steps are applicable when we wish to prove a specific fact:
- a hypothesis is made; this is a statement that we provide after some observations and we wish to either prove or deny it;
- multiple experiments are carried out in order to gather significantly substantial amount of data that can be then further analyzed and any tendencies can be noticed;
- based on the data gathered, conclusions are made: we either prove or deny the hypothesis. If hypothesis is proved, it may become a theory over long time.
In the context of this problem, we're at the first step where we make a hypothesis.
It's a chemical change because it's changing the object's property.
D) 250l
Explanation :
250,000/1000
