Which of the following is a synthesis reaction? a) 2h2 + o2 → 2h2o. b) 2h2o2 → 2h2o + o2. c) caco3 → cao + co2. d) 2agno3 + zn → 2ag + zn(no3)3

(apex) when a cup of water is dropped, as the cup falls, the water in the cup falls out true or false?

Abeaker with 2.00×102 ml of an acetic acid buffer with a ph of 5.000 is sitting on a benchtop. the total molarity of acid and conjugate base in this buffer is 0.100 m. a student adds 4.70 ml of a 0.360 m hcl solution to the beaker. how much will the ph change? the pka of acetic acid is 4.740.

When the chemicals iron sulfide (fes) and hydrochloric acid (hcl) are combined, bubbles appear from the mixture. 1. does the appearance of bubbles indicate a physical or chemical change? 2. why do the bubbles indicate this change? 3. what property is this?