The group of elements that have some properties of metals and some properties of nonmetals are called metalloids.
Answer:
1.65hr
Explanation:
Given parameters:
Number of labs = 5 labs
Time taken = 3 minutes
Unknown:
Time taken in hours to grade 165 labs = ?
Solution:
Let us find the rate of the teacher;
Rate =
Insert the parameters and solve;
Rate =
= 1.67labs/min
Now;
Time to grade 165 labs =
Time to grade 165 labs =
= 98.8min
Since;
60min = 1hr
98.8min =
= 1.65hr
A change in temperature is a sign that a chemical reaction has occurred. This occurs in an endothermic reaction. An endothermic process is any process which requires or absorbs energy from its surroundings, usually in the form of heat. It may be a chemical process, such as dissolving ammonium nitrate in water, or simply the melting of ice cubes.
Hopefully im not too late :/
<u>Answer:</u> The correct answer is Option A.
<u>Explanation:</u>
To calculate the number of moles of a substance, we use the equation:

We are given:
Given mass of fluorine = 6 grams
Now, to know the moles, we divide the given mass of fluorine by the atomic mass/molar mass of fluorine.
Thus, the correct answer is Option A.
To solve this problem, we must be given first the density
of air at 20 degrees Celsius. Looking up online, this is equal to:
density air (20C) = 0.0012041 g/mL
so that the volume is:
volume balloon = 0.57 g / (0.0012041
g/mL)
<span>volume balloon = 473.38 mL</span>