Which of the following measurements is written with two significant figures?

A. 0.00400 mL

B. 0.00404 mL

C. 0.00044 mL

D. 0.00440 mL

What is the pH of a solution has a hydrogen ion concentration of 6.3 x 10-10 M? Show work What is the pOH of the solution? Show work

Which of the following reactant pairs will not react together to produce a reaction? Rb + CaCl2 K + H2O Al + CoPO4 Ni + FeO

An element's atomic number is 63. How many protons would an atom of this element have?

The electrons in an atoms outermost orbitals, the electrons, are represented in a (n), which consists of the elements symbol, representing the atomic nucleus and inner-level electrons, and the appropriate number of dots.

According to the Pauli exclusion principle, when can two electrons occupy the same orbital? a) only if there is no place else to put them b) only if they have the same spin c) only if they opposite spins d) only if they're alike in all of their

Assuming that air contains 78 percent N2, 21 percent O2 and 1 percent Ar, all by volume. How many molecules of each type of gas are present in 1.0 L of air at STP?

Two children are playing tag. Child A who is doing the chasing can run 100m in 24 seconds Child B is running away from child A and can run 64m in 21 seconds.

What ion does a base increase

What is the definition of Amplitude?

An excess of NiCO3, 12 g, was added to 40cm cube of sulpheric acid, 2.0 mol/dm cube. The unreacted nickel carbonate was filtered out and the filtrate evaporated to optain the crystals.