A man checking the hardness of the water in an erlenmeyers flask-the water is soft due to the blue color
Somebody puts some chemicals into an Erlenmeyer flask to check the water hardness
A scientist holding an erlenmeyers flask and puts some chemicals into it to test the water hardness
A scientist in a lab putting some chemicals into an erlenmeyers flask due to test the hardness of the water - the water is soft and the content becomes blue
Time-lapse of a man checking the hardness of the water
A scientist is not satisfied with the water hardness test-the water is hard...
Scientist checking erlenmeyer flask with chemicals and writing results
Somebody pouring fresh water into an erlenmeyers flask
A scientist adds some water into an erlenmeyer flask
A man performing the water hardness test - the water is soft and good for use
A man performing the water hardness test - the water is soft and good for use
Female scientist mixing chemicals in erlenmeyer flask