How does an atom in ground state become excited?

Which of the following statements is true? Selected Answer: D. At least two of the above statements (A-C) are true. Answers: A. Ions are formed by adding or removing protons or electrons. B. Scientists believe that solids are mostly open space. C.

Metamorphic rocks that melt in a hot fluid can re-crystallize into a different form of rock. true or false

A student combined water, sugar, and salt in a beaker. Which of the following statements is true? A.) the individual substances can be separated by physical means B.) the individual substances cannot by separated by physical means C.

An element's most stable ion forms an ionic compound with bromine, having the formula XBr. If the ion of element X has a mass number of 85 and has 36 electrons, what is the identity of the element?

What is the difference between an exothermic and endothermic reaction.

Compare and contrast homogeneous and heterogeneous mixtures using key terminology, and provide at least three examples of each. For example, explain what the mixture is comprised of and what makes it homogeneous or heterogeneous.

Which element would most likely have chemical properties similar to that of fluorine (F) ?

Percentage compostion of carbon in CaCO3

Potassium iodide (ki) exhibits predominantly ionic bonding. the k and i ions have electron structures that are identical to which two inert gases?

Amino acid to protein as?