The enthalpy diagram to the right represents a set of thermochemical equations. Which set of equations could it represent? A + B Right arrow. C Delta. H1 = - 500 kJ
C + D Right arrow. E + 2F Delta. H2 = 100 kJ
F + D Right arrow. B Delta. H3 = 200 kJ

A + B Right arrow. C Delta. H1 = 800 kJ
C + D Right arrow. E + 2F Delta. H2 = - 200 kJ
F + D Right arrow. B Delta. H3 = - 300 kJ

A + D Right arrow. E Delta. H1 = 500 kJ
D Right arrow. F Delta. H2 = - 300 kJ

This large tectonic plate is bounded on three sides by whats know as the ring of fire. what is the name of this tectonic plate? a) pacific plate b) eurasian plate c) north american plate d) indo- australian plate plz it's science but there's no option for science so i picked chemistry

Answer asap need it by wednesday morning carry out the following calculations on ph and ka of from data. i. calculate the ph of 0.02m hcl ii. calculate the ph of 0.036m naoh iii. calculate the ph of 0.36m ca(oh)2 iv. calculate the ph of 0.16m ch3cooh which has ka = 1.74 x 10-5 mol dm-3 v. calculate ka for weak acid ha which has a ph of 3.65 at 0.30m concentration vi. calculate the ka of a solution made by mixing 15.0 cm3 0.2m ha and 60.0 cm3 0.31m a-. [ph= 3.80] vii. calculate the ph of a solution made by mixing 15.0 cm3 0.1m naoh and 35.0 cm3 0.2m hcooh. [ka = 1.82 x 10-4 m]

Why is the bottom layer of a trophic pyrimid the