Is calcium a element or compound

Q: What do you mean by atomic spectroscopy?

A: The study that involves the interaction of matter of different kinds and electromagnetic radiation…

Q: The radioactive element Carbon-14 has a half-life of approximately 5730 years. A fossil is measured…

A: For a radio active material the rate of decay is directly proportional to the Amount of the radio…

Q: Silicon and germanium are examples of

A: Silicon and Germanium are   good examples of Semiconductors

Q: Which of water, iron, ammonia, chromium, radon, and silicon are chemical compounds as opposed to…

A: We have to write the chemical compounds as opposed to elements

Q: Element X has 3 isotopes. One of the isotopes has a mass of 59.5 with an abundance of 43.3%. Another…

A: We know that, Average atomic mass of an element is a weighted average of all masses of all isotopes…

Q: A neutral atom of the element potassium (K) has A 19 protons. B. 20 neutrons. C. 39 electrons. 58…

A: No.of protons in an atom is determined by atomic number of that atom .

Q: Nuclear bombardment of the element molybdenum with deutrons resulted in the first synthetic element,…

A: Nuclear bombardment take place when reaction happens. Nuclei can undergo reactions which result in…

Q: name of the substance?

A:

Q: A carbon atom, with a half-full outer shell of electrons—four in a shell that can hold eight—readily…

A:

Q: Choose the BEST answer to the following. When food is exposed to gamma radiation, the food (a)…

A: Answer: bi,e doesn’t become radioactive.

Q: why the silcon crystal is preferred in the making of the electronic components

A: Required : Why the silicon crystal is preferred in the making of the electronic components

Q: Lithium has only two naturally occuring isotopes: lithiumi-6 and lithium-7.  Lithium-6 has a mass of…

A: The atomic mass of lithium can be determined by the following expression.

Q: Choose the BEST answer to the following. Which of these three elements has the most mass (a)…

A: The mass per nucleon for all the three elements is being evaluated for all the three elements as…

Q: Hydrogen escapes from the earth's atmosphere more readily than oxygen, Why?

A: As hydrogen has the least mass among all the elements, its mass is less than that of oxygen as…

Q: Why don't electrons in the atom enter the nucleus?

A: In electron capture, an atomic electron is absorbed by a proton in the nucleus, turning the proton…

Q: What do you understand by crystallography?

A: Crystallography is the study of crystals, their structures and properties. Crystals are arranged in…

Q: What is the most abundant element in the known universe?

A: There are 114 known elements in the universe.

Q: ス 3alte e Valt rass 2134

A: (a)Find the equivalent resistance of the given circuit for first path.

Q: Why are most of the solids crystalline in nature?

A:

Q: The radioactive element Carbon-14 has a half-life of approximately 5730 years. A fossil is measure…

A:

Q: Name three different types of evidence for the existence of atoms.

A: Following are the three different type of evidence that proves the existence of the atoms.…

Q: Elemental carbon has 6 protons and 6 neutrons. This is often described as carbon-12. Carbon-13 has 6…

A: Mass Number = Number of protons + Number of neutrons For Plutonium: Mass Number = 244 Number of…

Q: The atomic weight of hypothetical alloy is 77.4 g/mol, density is 8.22 g/cm', and atomic radius is…

A: given Atomic weight=77.4 g/molDensity (ρ)=8.22 g/cm3Atomic radius =0.125 nm

Q: Osmium has a density of 22.6 g/cm3. The mass of a block of osmium that measures 1.01 ст х 0.233 cm х…

A:

Q: . One isotope of oxygen has the atomic number 8 and the mass number 18. An atom of this isotope…

A: We know Isotopes have same atomic number (protons number ) but deferent mass number given oxygen has…

Q: Can gold be created from other elements ?

A: Gold is element whose atomic number is 79 and is represented by the symbol Au (which is the short…

Q: radioactive element Carbon-14 has a half-life of approximately 5730 years. A fossil is measured to…

A: Given  Half life time T1/2 = 5730 years  Remaining C -14 =( 80/100) N0

Q: Find in equivalent weight of KMnO4 in acidic and alkaline medium?

A: Answer In acidic medium the number electrons involved are 5. That is Mno4+BH++5e-→Mn2++4H2O…

Q: The different colours seen in exploding fireworks are produced using different elements. Element…

A: When a firework is exploded it reacts with oxygen. When it reacts with oxygen the electrons are…

Q: A 250g sample of Calcium-47 has a half-life of 4.536 ????. How much Calcuim-47 remains after six…

A: Given data:  Initial amount of calcium-47 (N0) = 250 g Number of half-lives (n) = 6 Required: The…

Q: Cobalt-60 has a half-life of approximately 5 years. If 53 g of the material was stored for 20 years,…

A: Half life period means the time taken for a radioactive material to be decayed to half of it's…

Q: What kind of basic force pulls electrons close to the atomic nucleus?

A: The positive charge of nucleus pulls the electrons close to the atomic nucleus. The nucleus of an…

Q: Element X has 2 isotopes. One of the isotopes has a mass of 18.9 with an abundance of 75.4%. The…

A: Given: Mass of the first isotope m1 = 18.9 with 75.4% of abundance Mass of the second isotope m2 =…

Q: half-life of an element is 20 years. In how many years will there be 12.5% of the initial material…

A: Given T1/2 = 20 years

Q: Acrylic bur is made from Titanium Gold Stainless steal Stone

A: Acrylic burs are made from stainless steel of good quality.

Q: The smallest unit of any element that retains the chemical properties of the element

A: The smallest unit of any element is its atom.

Q: sing nodal analysis.

A:

Q: You would like to fabricate p-type silocon. You should dope the material using: A Any atom, as long…

A: (C) An atom with 4 valence electrons

Q: this is one of the fundamental forces of nature that is responsible for radioactive decays in matter

A:

Q: Choose the best answer to the following: If two protons and two neutrons are removed from the…

A: Step 1Proton and neutron are respectively represented as

Q: Imagine you are a scientist and you are working with a museum on an archaeology exhibit. They tell…

A: Goven  Amount left N = (1/32 ) of initial  If initial amount is N0,  Then N = N0/32

The Bohr model

Students often get confused between Rutherford’s model and Bohr model of an atom. They interpret the postulates of both these models to be the same, which is incorrect. Rutherford’s model differs from Bohr’s model in the following ways: