What are the worst dangers of mixing bleach and ammonia-based cleaning solutions?

Aball bearing at 220.0 °c is dropped into a cup containing 250.0 g of water at 20.0 °c. the water and ball bearing come to a temperature of 30.0 °c. what is the heat capacity of the ball bearing in j/°c? (hint: how are the algebraic signs of q related for the ball bearing and the water? )

What is magnetic flux? explain faraday's law of induction.

Arock collection comes from which part of earth?