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)

How many moles are 6.022 (10^23) atoms of sodium

Summarize why a scientist measuring the diameter of an atom or the distance to the moon would use scientific notation

For which purpose do biochemists insert human genes into bacteria? to find a cure for the common cold to produce insulin for diabetics to kill resistant strains of bacteria to evolve certain species of bacteria

Mix 2g of hydrogen and 16g of oxygen what is the compound made

How is an unknown oxidation state of an element within a compound determined? a. it is determined from known oxidation state of an element within a compound determined b. it is always the same as the most likely oxidation state c.

What type of reaction is 2 NO2 - --> 2 O2 + N2

The main source of phosphorous is in: rocks water plants the atmosphe

To what part of a plant does the stem sliver water and nutrients

You place a balloon in a closed chamber at STP. When the balloon doubles in size, what happens to the chamber pressure? A.) The pressure stays the same B.) The pressure doubles C.) The pressure reduced by one half

2K3N + 3CaCrO4 → Ca3N2 + 3K, CrO Give the formula for the second reactant: How many potassium atoms on the reactant side: How many oxygen atoms on the product side?