The complete statement is "chemical properties can be observed only when the substance in a sample of matter are changing into different substance".
It states a key concept in chemistry.
A chemical property is the ability of a substance, element or compound, to <em>transform</em> into other substances either <em>by decomposing or by combining</em> with one or more substances.
This transformation is defined as chemical reaction.
During chemical reactions some chemical bonds are broken and others are formed leading to the formation of one or more different substances called products.
Some examples of chemical properties are: reactivity with oxygen, reactivity with water, acidity, basicity, oxidation, reduction. The only way to tell if a substance has certain chemical property is by letting it react and so observe the change of the original substance into one or more different substances.
Answer:
82 degrees
Explanation:
consider your staying point to be the center of a circle. this center has the coordinates (0, 0).
the radius of the circle is the distance you walked East (14 miles).
I assume your teacher means as "angle of displacement" the angle between the East-West line going through your starting point and the direct line from your starting point to your current position.
then the 100 miles North is tan(displacement angle)×14.
as it is the same, if you first went North and then East, or the other way around. you end up at the same point, with the same coordinates.
so, again.
100 = 14×tan(angle)
tan(angle) = 100/14 = 50/7 = 7.142857...
the displacement angle is then 82 degrees.
Hi!
I believe that there were the following options in this question:
<span>A) Which color bends the most to make a rainbow?
B) What color of scented marker has the best smell?
C) Which flower has the prettiest shade of purple on its petals?
D) What is the best-looking color on a high-performance sports car</span>
Now, options b), c) and d) are about a personal preference and opinion - they are not scientific uqestions.
The correct answer is a) - it asks about the properties of light.
Боже, как это сложно! Ну ладно.
Между прочим это ты сам должен делать, а то не куда не поступишь!
