(a) How many elements are found in period 4 in the periodic table? (b) How many elements are found in group 4A (or 14)?

Q: 5 g of anhydrous strontium nitrate is added to a beaker and exposed to the air. After several hours…

A: The percentage of water in hydrated sample is given as : Percentage of water = ( mass of water /…

Q: What element is found in period 4, group 4A? Use the atomic symbol to identify the element.

A: Given : Period of element is 4  Group of element is 4 A.

Q: The Group 1B metals, Cu, Ag, and Au, are calledcoinage metals. What chemical properties make…

A: The chemical properties of Group 1B metal that makes them suitable for making coins and jewelry has…

Q: Which of the following are poor conductors of heat and electricity? O Transition elements O Halogens…

A: Elements can be classified into 3 forms, that is metals, non-metals, and metalloids. Metals are the…

Q: Specify the number of protons and electrons in each of the following ions. A) Se^2−, needed for…

A: To specify the number of protons and electrons we will use the following concept . Since we know…

Q: 2. If you want to produce 85 g of silicon, how many grams of magnesium will you need? How many grams…

A: The chemical reaction that takes place between sand and magnesium metal to produce elemental silicon…

Q: A mass spectrometer is an instrument that allows scientists to determinethe presence of elements in…

A: The elements are arranged as the periodic function of atomic numbers.  The elements are arranged in…

Q: what mass of sodium is also produced?

A: Given :- 2Na3N → N2 + 6Na  Mass of N2 produced = 29.7 g  To calculate :-   Mass of sodium (in g)

Q: What is the % molecular mass of Iron in Fe2S3?

A: The percent mass of an element in a compound can be calculated by using the following formula:

Q: How many grams of iron are needed to combine with 24.6 g of O to make Fe2O3?

A:

Q: Which pair of elements would you expect to exhibit the greatest similarity in their physical and…

A:

Q: There are two naturally occurring isotopes of europium, 151Eu (151.0 amu) and 153EU (153.0 amu). If…

A: Given : There are 2 naturally occurring isotopes of europium. Mass of 151Eu = 151.0 amu Mass of…

Q: 2. Balance the following equations (in the formation of heavier elements). a.*He +He - Be b. “He +n…

A: Given nuclear equations are :  a). 4He + 4He -----------> Be  b). 4He + n -------------> 4He…

Q: Main-group elements are those in the columns 3A to 8A of the Periodic Table. True or Flase?

A: Representative elements are known as main group elements of the periodic table.

Q: What monatomic ions would you expect radium (Z = 88) and selenium (Z = 34) to form?

A: Monoatomic ions: These are the ions that consist of atoms of only one kind of element. The…

Q: 1 How does atomic theory account for the fact that when 1.000 g of water is decomposed into its…

A: Given, Mass of water = 1.00g Mass of H2 = 0.111 g Mass of O2 = 0.889 g The reaction for…

Q: The elements in Groups 1A(1) and 7A(17) are all quite reactive. What is a major difference between…

A: The elements in Groups 1A(1) and 7A(17) are all quite reactive. What is a major difference between…

Q: How many molecules are there in 1000 grams of  C12H22O11  or table sugar?

A: We have to calculate the  number of molecules in 1000 g of table sugar.

Q: How many atoms of O are found in 1.00 x 10 2 g of K 2Cr 2O 7 ?

A: Number of atoms of Oxygen present in the given compound can be calculated as -

Q: What is the mass % of H in C9H10N2?

A: Mass percentage is a kind of expressing the concentration of a solution. It gives an information…

Q: Which element would be expected to have chemical and physical properties closets to those nitrogen(N…

A: sulfur, because it's in the same groupGroups are columns of a periodic table. Both oxygen and sulfur…

Q: The vitamin niacin (nicotinic acid, C6H5NO2) can be isolated from a variety of naturalsources such…

A: To find: The source of nicotinic acid which is best for use in a multivitamin tablet.

Q: 2b. A student formulates the following hypothesis: "If phosphorus were to form a positive ion, P**,…

A: The atomic radius of an element is provided as the distance between the center of the nucleus and…

Q: What is the mass in grams of 2.00 × 105 atoms of naturally occurring neon?

A: Given : Number of atoms of neon i.e Ne = 2.00 X 105 atoms.

Q: With the advent of techniques such as scanning tunneling microscopy, it is now possible to “write”…

A: Given:Surface is 20 atoms high and 14 atoms wide.Number of Platinum atoms = 20 atoms × 14 atoms =…

Q: Of the elements Be, C, Cl, Sb, and Cs, which is most likely to be a metalloid?

A:

Q: Matter is defined as ....... إجابتك Felite is إجابتك

A: 2. The term matter refers to anything that occupies space and has mass—in other words, the “stuff”…

Q: You have 3.31 L of water that contains 25 mg/L of PO43-. What is the total amount of phosphate in…

A: • The values provided in the question are:-    i) Density of phosphate ion solution,d  = 25 mg/L…

Q: what is the mass percentage of water in Zn(NO3)2*6H2O?

A: Mass percentage of water = Mass of waterMass of Zn(NO3)2.6H2Ox100There are total six water molecule…

Q: How many grams of iron are needed to combine with 26.3 g of O to make Fe2O3?

A:

Q: C. What is the weight of ferrous sulfate FeSOa.7H: 0 should be taken to designate iron as ferric…

A: Recall the following reaction that will occur on heat of hydrated ferrous sulphate      FeSO4.7H2O…

Q: An atom has a very small nucleus surrounded by an electron "cloud." The figure below represents the…

A: The diameter of the nucleus is given that 2 mm. The electron cloud or diameter of atom is 200m. That…

Q: Which of the following elements is not a representative element? O Nickel Cadmium Silicon O Barium

A: I A, IIA, IIIA, IV A, VA, VI A, VII A, VIII A elements are called representative elements. Between…

Q: Consider Cr-54, Fe-54, Fe-58 and Ni-58 , which of this are isobars and which are isotopes

A:

Q: There are two naturally occurring isotopes of europium, 151Eu(151.0 amu) and 153Eu(153.0 amu). If…

A: Given information:Two isotopes of europium, 151Eu (151.0 amu) and 153Eu (153.0 amu)Atomic mass of Eu…

Q: does hydrogen exist as an atomic element in the air?

A: Interpretation: Does hydrogen gas exist as an atomic element in the air is to be determined.

Q: how many atoms per particle in sulfur(s8)?

A: Atomic mass of sulfur = 32g Molecular mass of S8 =8×32=256g

Q: Which of the highlighted elements in Figure P2.7 is (a) a reactive nonmetal, (b) a chemically inert…

A: Reactive metals exist in group 1 of the long form of periodic table. Group 1 is placed at the…

Q: if the density of an element 1.5 g/ml with volume 1.8 L, its mass will be .. 2700 O 2.7 O 1200 1.2…

A: Given question is asking about the mass of substance, if density and volume of solution is present .…

Q: 1. How does atomic theory account for the fact that when 1.000 g of water is decomposed into its…

A: The atomic theory was first proposed by John Dalton in the year 1803.

Q: the measured EA of Na is -53 KJ/mol. What is the physical meaning of the fact that the EA is a…

A: EA means the electron affinity .  The amount of heat is released when 1 electron is added to the…

Q: What is a period in the periodic table? From what does it derive its name?

A: The elements are arranged in a periodic table. The properties of elements have been studied and…

Q: Given that you had 1 mol glucose (C 6H 12O 6), what would the mole ratio of glucose to oxygen be?

A: Balance Chemical equation means number of atoms or ions should be equal in both side (reactant and…

Q: To what weight of AICI3 would 0.280 g of AgCl correspond? Atomic weights for Ag = 108, Cl = 35, Al =…

A: Molecular weight of AgCl = (108 + 35 ) = 143 g/mol  So, 143 g AgCl = 1 mol AgCl  1 g AgCl = 1/143 =…

Q: A 67.2 g sample of a gold and palladium alloy contains 3.07×1023 atoms . What is the mass…

A: Given : Mass of sample = 67.2 g And total number of atoms = 3.07 X 1023 atoms Assuming the moles of…