What mineral is this? egg-sized piece. transparent pink color with glassy luster. shows conchoidal fracture. the hardness is 7.

Pink Quartz

Explanation:

Quartz. Can come on different colours like pink, white, gray, purple, black, yellow or green.

Luster means Appearance, Quartz unlike Silica, looks like glass.

Conchoidal fracture: It´s  how Quartz´s surface fractures on a smoothly curved way.

Hardness is mineral´s property of being scratched by others. Mohs scale of mineral hardness is used to classify a mineral as softer or not. In this case, quartz has a hardness of 7, that means it´s quite hard, since the scale starts in 1 and finishes in 10.

when [oh-] is 10-5  m, and [h3o+] is 10-9  m, the poh is 5 and ph is 9. again in both cases the sum of ph and poh is 14. however, the hydrogen ion concentration is not always going to be equal to exactly 1 x 10 raised to a negative number. for example, we skipped over the value of 2.0 x 10-7.