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Alpha,beta and gamma particles

The answer is Fe+3 cation and SO4–2 anion.

परमाणु द्रव्यमान का सीधा मतलब होता है किसी एक परमाणु का द्रव्यमान । हम जानते हैं कि किसी तत्व का परमाणु अतिसूक्ष्मतम कण होता है और इसे किसी तराजू पर तौलना अथवा मापना संभव नहीं है। इसलिए किसी परमाणु का द्रव्यमान किसी दूसरे परमाणु के द्रव्यमान के सापेक्ष ज्ञात किया जाता है।

रसायन विज्ञान के अन्तर्राष्ट्रीय संगठन (IUPAC) ने एक अन्तर्राष्ट्रीय आम सहमति के आधार पर कार्बन परमाणु के द्रव्यमान के बारहवें भाग को इकाई चुना। कहने का तात्पर्य यह है कि कार्बन-12 के एक परमाणु में 6 प्रोटॉन एवं 6 न्यूट्रॉन होते हैं जिससे इसकी द्रव्यमान संख्या 12 होती है | इसलिए इसे ठीक 12 परमाणु द्रव्यमान मात्रक (atomic mass unit-amu) द्रव्यमान दिया गया है।

संयोजकता- किसी तत्व के परमाणु द्वारा दिए जाने, लिए जाने या साझेदारी किए जाने वाले इलेक्ट्रॉन की संख्या, उस तत्व की संयोजकता कहलाती है।

हम जानते हैं कि किसी रासायनिक अभिक्रिया में केवल बाह्यतम कक्ष में उपस्थित इलेक्ट्रॉन या संयोजकता इलेक्ट्रॉन ही भाग लेते हैं। अत: संयोजकता निर्धारण में संयोजकता इलेक्ट्रॉन ही महत्त्वपूर्ण होते हैं। यदि किसी तत्त्व के परमाणु के संयोजकता इलेक्ट्रॉन 1, 2 या 3 हैं तो उसकी संयंजकता क्रमशः 1, 2 या 3 होगी। यदि तत्व के बाह्यतम कक्ष में 4 से 8 इलेक्ट्रॉन हैं तो उसकी संयोजकता (संयोजकतां इलैक्ट्रॉन-8) होगी।

उदाहरणार्थ- क्लोरोन या फ्लोरीन के बाह्यतम कक्ष में 7 इलेक्ट्रॉन हैं, तब उनकी संयोजकता 7-8 =-1 होगी। अतः क्लोरीन या फ्लोरीन के आयन को Cl⁻ या F से प्रदर्शित करेंगे।

संयोजकता- किसी तत्व के परमाणु द्वारा दिए जाने, लिए जाने या साझेदारी किए जाने वाले इलेक्ट्रॉन की संख्या, उस तत्व की संयोजकता कहलाती है।

हम जानते हैं कि किसी रासायनिक अभिक्रिया में केवल बाह्यतम कक्ष में उपस्थित इलेक्ट्रॉन या संयोजकता इलेक्ट्रॉन ही भाग लेते हैं। अत: संयोजकता निर्धारण में संयोजकता इलेक्ट्रॉन ही महत्त्वपूर्ण होते हैं। यदि किसी तत्त्व के परमाणु के संयोजकता इलेक्ट्रॉन 1, 2 या 3 हैं तो उसकी संयंजकता क्रमशः 1, 2 या 3 होगी। यदि तत्व के बाह्यतम कक्ष में 4 से 8 इलेक्ट्रॉन हैं तो उसकी संयोजकता (संयोजकतां इलैक्ट्रॉन-8) होगी।

उदाहरणार्थ- क्लोरोन या फ्लोरीन के बाह्यतम कक्ष में 7 इलेक्ट्रॉन हैं, तब उनकी संयोजकता 7-8 =-1 होगी। अतः क्लोरीन या फ्लोरीन के आयन को Cl⁻ या F से प्रदर्शित करेंगे।

The rate-determining step is defined as the slowest step in a chemical reaction which determines the speed at which the overall reaction takes place.

The rate-determining step is used for deriving the rate of the equation for a given chemical reaction.

The rate of the equation is given as:

rate = k₁ [A]²

The property of certain solution which resist the change in pH on addition of small amount of acid (or) alkali to it.

If a system in equilibrium is subjected to a change of concentration, temperature (or) pressure, the equilibrium shifts in a direction so as to undo the effect of the change imposed.

K_w = [H₃O⁺][OH^–] = 10^-14

Taking log of minus sign

-log K_w = – log(H₃O⁺) (OH^–)

-log K_w = – log[H₃O⁺] – log [OH^–]

PK_w = P_H + P_OH = 14

p_H + p_OH = 14

Ionic product of water may be defined as product of molar concentration of hydrogen ion and hydroxyl ion concentration at a given temperature.

K_w = [H₃O⁺][OH^–] = 10^-14

(i) open system

(ii) isolated system.

If a system under equilibrium is subjected to a change in temperature, pressure or concentration, then the equilibrium shifts itself in such a way so as to neutralise the effect of the change.

Temporary Hardness – presence of dissolved Bicarbonates of Mg and Ca. 

Permanent Hardness – Presence of dissolved Chlorides and sulphates of Mg and Ca.

From Boyle’s law V ∝ 1/p  .....(1)

From Charle’s law V ∝ T …..(2) 

From(1) and (2)

V ∝ T/P

PV ∝ T 

Or PV – RT

It is the tendency of atom to attain 8 electrons in valence shell.

Both forward and backward reactions are occurring at the same rate.

Lithium shows similarities to magnesium and beryllium to aluminium in many of their properties. This type of diagonal similarity is commonly referred to as diagonal relationship in periodic table.

Chromatography is used to: 

• Separate mixtures into their components 
• purify components 
• test the purity of compounds

Diamagnetic.

a. Increase the amount of product 

b. Increase the amount of product 

c. Decrease the amount of product, 

d. Increase the amount of product

Pressure — Pressure has no effect here. Because the number of molecules in the reactants and products side are equal. T

Temperature — Here the forward reaction is endothermic. So increasing temperature increases the rate of forward reaction. Decreasing temperature decreases the rate of forward reaction.

Statements b, c, d are correct.

Hydrogen has atomic number 1. It has monatomic form is the most abundant chemical substance and it has single proton and zero neutrons. It exists in diatomic form.

1. Forward reaction is an exothermic. 

2. Number of reactant and product molecules

a. Speed of forward reaction increases 

b. Speed of forward reaction increases 

c. Speed of forward reaction increases

a. B – Forward reaction, C – Backward reaction 

b. Equilibrium 

c. No At equilibrium rate of both forward and backward reactions are equal.

1. Total number of moles of the reactant = 4

2. 2

Backward reaction.

On every collision there is loss of energy, so molecule s would have slowed down and settled down in vessel and pressure reduce to Zero.

a. True. Optical density = log₁₀ Io/In, where Io is the intensity of incident light and In is the intensity of transmitted light. 

b. False. The optical densities for each layer are cumulative so that, for the same level of exposure, the densities are increased compared with using a single layer. 

c. True. Referring back to the equation in (a), if the optical density = 1, then only 10% of light is transmitted, as log₁₀ 10 =1. Likewise, if optical density = 2, then only 1% of light is transmitted (log₁₀ 100 = 2). 

d. False. Optical densities of around 2 may be seen with normal illumination; however, an optical density of 3 appears very dark and requires the use of a focal bright light to see through it. An optical density of 4 means that only 1/10,000 of the incident light has been transmitted, so the film will appear black. 

e. True. Contrast may be measured as the difference in optical densities: OD₁ – OD₂. This difference will be produced by the nature of the tissue being imaged.

a. False. This refers to the inherent optical density of the film material plus unexposed developed emulsion. This should be less than 0.2. However, film that has been stored for too long a period or at too high a temperature may have higher values, in which case it should not be used. 

b. False. Film speed is a measure of film sensitivity when exposed, i.e. a high-speed film requires less exposure to produce a certain optical density than a film of low speed.

c. True. Films with narrow latitude require a smaller range of exposures to achieve darkening over the useful optical density range, i.e. they provide good contrast between tissues. Wide-latitude films are the reverse, requiring a greater range of exposures to achieve this range. 

d. True. Film gamma refers to the slope of the linear part of the characteristic curve and is the ratio of the differences between optical density and film exposure at two given points on the slope. If gamma increases, then film latitude decreases and contrast increases. These are inherent properties of any given film. 

e. True. The optical densities for each layer are cumulative so that, for a given exposure, the total optical densities will be greater than using a single layer. This assumes that the total thickness of emulsion is doubled.

a. False. Most films usually have a double layer of emulsion attached to a polyester film base. This allows increased speed as two intensifying screens can be used. Mammography films usually are single-layered. 

b. False. Silver bromide is most commonly used. 

c. True. The larger the grain size, the faster the film. Larger grains provide a larger target for the light photons and so fewer photons are required to produce the image. 

d. False. Both the anion (bromide) and cation (silver) are required to produce the latent image: the bromide is the electron donor and the silver ion becomes deposited and later converted to the black silver atom to produce the image. 

e. False. Post-processing is vital in converting the latent image to a visible image. This requires the conversion of silver ions to visible silver atoms (electron gain) from electron donors (e.g. phenidone and hydroquinone), a process known as film development. Unexposed grains also need to be removed from the film (to render the film stable in light) and the process of development halted to prevent fogging, a process known as fixing.

a. False. Noise will increase as a proportion of the number of photons (n) that are detected in the image (as noise = √n). 

b. True. Although the amount of noise will increase with increasing patient dose, the actual SNR increases and so improves image quality. 

c. False. Noise is more significant. Differentiating between the nature of soft-tissue structures is more important when there is less inherent contrast within the tissues being imaged. Therefore, noise will prevent this differentiation. 

d. True. 

e. False. The higher film gamma produces more radio graphic contrast within the film for the same exposure, but also has the same effect on the noise, which is displayed in the image.

a. True. 

b. False. 

c. False. 

d. True. 

e. True. Data content increases due to an increase in matrix size.

c) Movie/ multimedia files

swf, .wav, .mp3, and .mp4 are examples of Movie/ multimedia files.