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The most abundant element in the Earth’s crust by mass is _____.

Isotopes of an element have the same number of _____ but a different number of _____.

Which of the following is not true of an atom that has an atomic number of 19 and a mass number of 41?

How many protons (p), neutrons (n), and electrons (e) are in an atom of 235U?

What is the standard SI unit for length?

The simplest form of a substance is known as a(n) _____.

In a scientific method, a hypothesis is tested by a(n) _____.

Which of these substances are mixtures? I. Steam II. Crude oil III. Salt water IV. Gun powder V. Oxygen VI. Mercury

1.  Answer the following questions for an atom of magnesium.     A.  The atomic number of magnesium is ________ and magnesium contains _______ protons and ________ electrons.     B.  The electron configuration for magnesium is:          1st energy level = ____ electrons   2nd energy level = ____ electrons 3rd energy level = ____ electrons     C.  An atom of magnesium has ______________ valence electrons.     D.  A particular isotope of magnesium has a mass number of 26.  (26Mg)           This isotope contains ______ protons,  __________electrons, and __________ neutrons.     E.  Magnesium is a member of the _________ family of elements.     F.  When magnesium forms an ion is will have a _____________ charge.  (negative 1, negative 2, positive 1, positive 2   2.  1 mole of sulfur has a mass of _____________ g.   3.  How many moles of iron are there in a nail weighing 5.75 g?  Show the set up for credit.  (Assume this nail is pure iron.)

1.  Answer the following questions for an atom of chlorine.     A.  The atomic number of chlorine is ________ and chlorine contains _______ protons and ________ electrons.     B.  The electron configuration for chlorine is:          1st energy level = ____ electrons   2nd energy level = ____ electrons 3rd energy level = ____ electrons     C.  An atom of chlorine has ______________ valence electrons.     D.  A particular isotope of chlorine has a mass number of 37.  (37Cl)           This isotope contains ______ protons,  __________electrons, and __________ neutrons.     E.  Chlorine is a member of the _________ family of elements.     F.  When chlorine forms an ion is will have a _____________ charge.  (negative 1, negative 2, positive 1, positive 2   2.  1 mole of calcium has a mass of _____________ g.   3.  How many moles of carbon are there in a diamond weighing 1.75 g?  Show the set up for credit.