Concept explainers
Interpretation:
The number of electrons, protons and neutrons present in atom of Technetium
Concept Introduction:
Electrons:
Electrons are constituents of an atom and it is the negatively charged subatomic particle. It is known as the elementary particle because it cannot be broken down into smaller particles.
Charge of the electron
Mass of the electron
Protons:
Hydrogen atoms had the smallest mass to charge ratios, indicating that they must be the positively charged fundamental particles of atomic structure. Such a particle is called a proton.
Charge of the proton
Mass of the proton
Neutrons:
It is a sub-atomic particle in an atom which having neutral charge. They are not positive like protons.
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Chemistry: The Molecular Science
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- Copper atoms. (a) What is the average mass of one copper atom? (b) Students in a college computer science class once sued the college because they were asked to calculate the cost of one atom and could not do it. But you are in a chemistry course, and you can do this. (See E. Felsenthal, Wall Street Journal, May 9, 1995.) If the cost of 2.0-mm diameter copper wire (99.9995% pure] is currently 41.70 for 7.0 g, what is the cost of one copper atom?arrow_forwardAtomic structure. (a) The synthetic radioactive element technetium is used in many medical studies. Give the number of electrons, protons, and neutrons in an atom of technetium-99. (b) Radioactive americium-241 is used in house-hold smoke detectors and in bone mineral analysis. Give the number of electrons, protons, and neutrons in an atom of americium-241.arrow_forwardThe photo here depicts what happens when a coil of magnesium ribbon and a few calcium chips are placed in water. (a) Based on these observations, what might you expect to see when barium, another Croup 2A element, is placed in water? (b) Give the period in which each element (Mg. Ca, and Ba) is found. What correlation do you think you might find between the reactivity of these elements and their positions in the periodic table?arrow_forward
- The vitamin niacin (nicotinic acid,C6H5NO2 ) can he isolated from a variety of natural sources, such as liver, yeast, milk, and whole grain. It also can be synthesized from commercially available materials. Which Source of nicotinic acid, from a nutritional view, is best for use in a multivitamin tablet? Why?arrow_forwardCopper: (a) Suppose you have a cube of copper metal that is 0.236 cm on a side with a mass of 0.1206 g. If you know that each copper atom (radius = 128 pm) has a mass of 1.055 1022 g (you will learn in Chapter 2 how to find the mass of one atom), how many atoms are there in this cube? What fraction of the cube is filled with atoms? (Or conversely, how much of the lattice is empty space?) Why is there empty space in the lattice? (b) Now look at the smallest, repeating unit of the crystal lattice of copper. Knowing that an edge of this cube is 361.47 pm and the density of copper is 8.960 g/cm3, calculate the number of copper atoms in this smallest, repeating unit.arrow_forward
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