The electron configuration below represents what element? 1s22s22p63s23p64s2

Which of the following materials is a metalloid or semi-metal (has some metallic properties and some properties similar to non-metals) ? Group of answer choices Na silicon (Si) NaCl selenium (Se)

A 275-mL flask contains pure helium at a pressure of 752 torr. A second flask with a volume of 475 mL contains pure argon at a pressure of 722 torr.

Find the mass (grams) in 2.60 mol of lithium?

Which basic property determines a colored light's placement on the spectrum of visible light? A:Speed B:frequency C:amplitude D:velocity

For each pair, which has higher potential energy? (a) The fuel in your car or the gaseous products in its exhaust (b) Wood in a fire or the ashes after the wood burns

Calculate the empirical formula from the given percent compositions. 82% nitrogen (N), 18% hydrogen (H)

Atoms of different isotopes of the same element differ in their total number of electrons neutrons protons valence electrons

Which type of electromagnetic radiation has the longest wavelength? A) ultraviolet B) infrared C) X-ray D) visible

Pretend the coastal town of Galveston, TX has decided to install new wave generators on all its beaches to create energy for the entire island. What disadvantages might arise?

Using a balanced chemical reaction and a periodic table, which of the following is not possible to calculate?