If the bill is counterfeit and the paper is wood-based, the iodine in the pen solution will react with the starch and leave a dark brown or black mark.
Answer:
This is easy, CO2 is (Carbon Dioxide) a main cause of air pollution. We put it in the air every day when we drive cars or vehicles. And from wildfires and volcanoes, but they rarely erupt now.
Explanation:
Answer:
(3) 4 cm' and 2.0 g/cm3
Explanation:
Given:
volume= V= 8 cm³
mass= m= 16 g
The density is the mass per volume of a substance, so the density of the rock is:
density= d= 16 g/8 cm³= 2 g/cm³
When we cut the rock in half, we have a half volume and a half mass:
V= 8 cm³/2= 4 cm³
m= 16 g/2= 8 g
But the density is not altered because it is an intrisic property - it does not change with the amount of subtance. Thus, the density of a half rock is:
d = m/V= 8 g/4 cm³= 2 g/cm³
Right amount of water is the secret.
