Please show the calculations. 1) 1.3 g of zinc reacts with excess sulphuric acid. Calculate the volume of hydrogen gas formed at s. tp. (Zn = 65, 1 mole of gas occupies a volume of 22.4 dm³ at s. t.p.).
A. 112cm³
B. 224cm³
C. 336cm³
D. 448cm³
2) Calculate the volume of sodium hydroxide of concentration 0.5 mol dm¯³ needed to neutralize 25.0cm³ sulphate acid of concentration 0.20mol dm¯³.
A. 10cm³
B. 20cm³
C. 25cm³
D. 50cm³​

Find the mass in grams of 1.37x1020 particles of h3po4

Phosphoric acid is a triprotic acid ( =6.9×10−3 , =6.2×10−8 , and =4.8×10−13 ). to find the ph of a buffer composed of h2po−4(aq) and hpo2−4(aq) , which p value should be used in the henderson–hasselbalch equation? p k a1 = 2.16 p k a2 = 7.21 p k a3 = 12.32 calculate the ph of a buffer solution obtained by dissolving 18.0 18.0 g of kh2po4(s) kh 2 po 4 ( s ) and 33.0 33.0 g of na2hpo4(s) na 2 hpo 4 ( s ) in water and then diluting to 1.00 l.

Which proportionality applies to avogadro’s law?