How cold does it have to be for water to freeze instantly

It is important to wear proper protective equipment in lab even when not actively performing experiments because accidents can affect any researcher, even one not working on an experiment. select the best answer from the choices provided

If 3.00 g of titanium metal is reacted with 6.00 g of chlorine gas, cl2, to form 7.7 g of titanium (iv) chloride in a combination reaction, what is the percent yield of the product?

What layer of the atmosphere is directly above the troposphere?