Answer:
I might be late but when red paint and blue paint mix to become purple. its a <u>physical change</u>, so its C
Explanation:
Answer:
We have 1.361 moles in the sample
Explanation:
Mass of iron = 76.02g
Molar mass of iron = 55.845 g/ mole ( This we can find in the periodic table, and menas that 1 mole of iron has a mass of 55.845 g).
To calculate the number of moles we will use following formula:
moles (n) = mass / molar mass
moles iron = 76.02g / 55.845 g/ mole
moles iron = 1.36127 moles
To use the correct number of significant digits we use the following rule for multiplication and division :
⇒ the number with the least number of significant figures decides the number of significant digits.
⇒76.02 has 4 digits ( 2 after the comma) and 55.845 has 5 digits (3 after the comma).
⇒ this means 1.361 moles
We have 1.361 moles in the sample
Answer:
29 mL
Explanation:
<h3>Equation</h3>
The question needs us to find the volume of the liquid. The equation for volume using density and mass is:
Volume = Mass / Density
<h3>Solve</h3>
We can substitute the given values for density and mass into the equation:


<h3>Additional Comments</h3>
The answer we obtained (29 mL) is rounded to two significant figures. When multiplying or dividing, the amount of significant figures in the final answer is always the least amount of significant figures in one of the values.
Below are the significant figure rules:
Nonzero digits will always be significant (eg. 54 --> 2 significant figures)
Zeroes at the beginning of a number will never be significant (eg. 0.1 --> 1 significant figure)
Zeroes between two nonzero digits will always be significant (eg. 504 --> 3 significant figures)
Zeroes following a number will always be significant if the number contains a decimal point (eg. 40.0 --> 3 significant figures)
Answer:
Humidity is the amount of moisture (water vapor) in the air. It can be expressed as absolute humidity or relative humidity. Absolute humidity is the mass of water vapor divided by a unit volume of air (grams of water/cm3 of air).
An insect needs mud wallows to breed; that insect pollinates several flowers in that ecosystem.