Why must a ph meter be calibrated by using a solution with a known ph value

There is an area in idaho named craters of the moon where most of the ground is covered with basalt, adark gray, igneous rock with no visibl crystals. what can you infer about the geographical history of the area?

If 1.8 l of water is added to 2.5l of a 7.0 molarity koh solution, what is the molarity of the new solution

Be sure to answer all parts. the following equilibrium constants were determined at 1123 k: c(s) + co2(g) ⇌ 2co(g) k'p = 1.30 × 1014 co(g) + cl2(g) ⇌ cocl2(g) k''p = 6.00 × 10−3 calculate the equilibrium constant at 1123 k for the reaction: c(s) + co2(g) + 2cl2(g) ⇌ 2cocl2(g) 4.68 × 10 9 (enter your answer in scientific notation.) write the equilibrium constant expression, kp: