Which equation below is correctly balanced? A 2Na + O2 ---> 2Na2O
B Sn + 2KOH ---> K2SnO2 + 2H2
C AsCl3 + 3H2O ---> 3HCl + As(OH)3
D H2 + O2 ---> H2O

The starship enterprise is caught in a time warp and spock is forced to use the primitive techniques of the 20th century to determine the specific heat capacity of an unknown mineral. the 125-g sample was heated to 96.3°c and placed into a calorimeter containing 85.9 g of water at 20.0°c. the heat capacity of the calorimeter was 14.2 j/k. the final temperature in the calorimeter was 24.5°c. what is the specific heat capacity (in j/g°c) of the mineral? enter to 4 decimal places.

An electron with a charge of -1.6 × 10^-19 coulombs experiences a field of 1.4 × 10^5 newtons/coulomb. what is the magnitude of the electric force on this electron due to this field? a. 1.6 × 10^-3 newtons b. 1.4 × 10^24 newtons c. 2.2 × 10^-14 newtons d. 7.4 × 10^-13 newtons e. 4.5 × 10^14 newtons

Aspring with an unstrained length of 0.071 m and a spring constant of 2.6 n/m hangs vertically downward from the ceiling. a uniform electric field directed vertically upward fills the region containing the spring. a sphere with a mass of 5.29 10-3 kg and a net charge of +7.2 µc is attached to the lower end of the spring. the spring is released slowly, until it reaches equilibrium. the equilibrium length of the spring is 0.058 m. what is the magnitude of the external electric field?