10. What procedure is safest to follow when using an open flame to heat the contents of a test tube that contains a flammable mixture?
O A. Cork the test tube and then heat it gently near the bottom only.
O D. Cork the test tube and place it in a beaker of water, then heat the water in the beaker.
C. Heat the open test tube gently near the bottom only.
O B. Place the open test tube in a beaker of water, then heat the water in the beaker.

Cork the test tube and then heat it gently near the bottom only.

Explanation:

If the contents of the test tube is flammable, then it can catch fire easily at any time. In that case, we can not heat the mixture in an open test tube, that will make the flammable substance to catch fire easily.

In heating such a flammable material, the test tube should be securely corked and heat is delivered gently to the bottom of the tube. This will prevent the substance from bursting into flames spontaneously.

20 drops hope this