Which of these equations is balanced? a. 3 H2SO4 + 2Al → Al2 (SO4) 3 + 3H2 b. 2KCl + Pb (NO3) 2 → KNO3 + PbCl2 a b a and b neither

Students in a science class learn that groundwater is an important source of drinking water for many communities. They construct a model to study how leaking chemicals from a landfill can affect groundwater.

Kendall wants to determine if there is a trend in air temperature changes during April. Which procedure should she chose? A) measure the temperature every hour for 1 day B) measure the temperature at noon everyday P. S This is Science

In an ionic compound, the size of the ions affects the internuclear distance (the distance between the centers of adjacent ions), which affects lattice energy (a measure of the force need to pull ions apart), which affects the enthalpy of solution.

Uranium-238 decays to Lead-206. Both Rock X and Rock Y initially had a ratio of 100%. Uranium-238 to 0% Lead-206. Today, Rock X has a ratio of 50%. Uranium-238 to 50% Lead-206. Rock Y has a ratio of 25% Uranium-238 to 75% Lead-206.

An irrelgular object with a mass of 118g displaces 25ml of water when placed in a graduated cylinder. What is the density

Two compound samples are found to have the same mass percentages of the same elements. what can you conclude about the two samples

Sodium hypochlorite (Na xCl yO z) is the active ingredient in household bleach. A 250.0 g sample of sodium hypochlorite contains 77.2 g sodium, 119.1 g chlorine, and the remainder is oxygen. Calculate the empirical formula of sodium hypochlorite.

The tapeats sandstone in the grand canyon is an example of a clastic sedimentary rock. such clastic sedimentary rocks can be distinguished from biochemical sedimentary rocks by

An ice cube and a scoop of table salt are left outside on a warm, sunny day. Explain why the ice cube melts and the salt does not

Which atomic orbitals overlap to form the C-O bond of dimethyl ether, (CH3) 20? O c 2sp^3 + 2sp^3 OC 2sp^2 + 0 2p O c 2sp^2 + 0 25p^2 O C 2sp^3 + O 2sp?