Examples of ratio in the following topics:
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- Molar ratios, or conversion factors, identify the number of moles of each reactant needed to form a certain number of moles of each product.
- From this reaction equation, it is possible to deduce the following molar ratios:
- These molar ratios can also be expressed as fractions.
- These molar ratios will be very important for quantitative chemistry calculations that will be discussed in later concepts.
- Calculate the molar ratio between two substances given their balanced reaction
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- The law of multiple proportions states that elements combine in small whole number ratios to form compounds.
- The law, which was based on Dalton's observations of the reactions of atmospheric gases, states that when elements form compounds, the proportions of the elements in those chemical compounds can be expressed in small whole number ratios.
- In CO2, the ratio of the amount of oxygen compared to the amount of carbon is a fixed ratio of 1:2, a ratio of simple whole numbers.
- In CO, the ratio is 1:1.
- Dalton's law of multiple proportions is part of the basis for modern atomic theory, along with Joseph Proust's law of definite composition (which states that compounds are formed by defined mass ratios of reacting elements) and the law of conservation of mass that was proposed by Antoine Lavoisier.
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- The law of definite composition states that chemical compounds are composed of a fixed ratio of elements as determined by mass.
- It stated that chemical compounds are formed of constant and defined ratios of elements, as determined by mass.
- Therefore, by mass, carbon dioxide can be described by the fixed ratio of 12 (mass of carbon):32 (mass of oxygen), or simplified as 3:8.
- Berthollet supported the concept that elements could mix in any ratio.
- The law of definite composition has applications to both molecular compounds with a fixed composition and ionic compounds as they require certain ratios to achieve electrical neutrality.
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- Mass spectrometry has been used to study the ratio of carbon isotopes in various plants to understand the mechanisms of photosynthesis.
- Mass spectrometry has been used to study the ratio of isotopes in various plants to understand the mechanisms of photosynthesis.
- Grasses in temperate environments, such as barley, rice, and wheat, follow a C3 photosynthetic pathway that yields distinctive isotopic ratios.
- Grasses in hot, arid environments, specifically maize, but also millet, sorghum, sugar cane, and crabgrass, follow a C4 photosynthetic pathway that produces higher ratios of 13C to 12C.
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- A compound's empirical formula is the simplest integer ratio of its constitutional chemical elements.
- For example, water is always composed of a 2:1 ratio of hydrogen to oxygen atoms.
- Ethyl alcohol, or ethanol, is always composed of carbon, hydrogen, and oxygen in a 2:6:1 ratio; this does not uniquely determine the kind of molecule, however.
- Dimethyl ether, for example, has the same ratios as ethanol.
- For example, carbohydrates have the same ratio (carbon: hydrogen: oxygen = 1:2:1) and thus the same empirical formula, but have different total numbers of atoms in the molecule.
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- The ratios used are based upon the units and are set up so that the units in the denominator of the ratio match the numerator units of the given and the units in the numerator of the ratio match those in either the next ratio or the final answer.
- Then find a ratio that will help you convert the units of grams to atoms.
- As you probably have already guessed, you need to use a couple of ratios to help you in this problem.
- The ratio that 4.002 g of He = 1 mole (molar mass) will help you in this problem.
- Expressing this as a proportion or ratio, there is one mg per 10-3 grams, or 1000 mg/1 g.
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- The pH of a buffer depends on the ratio [base]/[acid] rather than on the particular concentration of a specific solution.
- The pH of a buffer depends on the ratio [base]/[acid] rather than on the particular concentration of a specific solution.
- Therefore, you need only to adjust the ratio of [C2H3O2-]/[HC2H3O2] to get the desired final hydrogen ion concentration.
- To satisfy the expression, the ratio of [C2H3O2-]/[HC2H3O2] must be 0.36 to 1.
- The more the ratio needs to differ to achieve the desired pH, the less effective the buffer.
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- Combustion analysis is commonly used to determine the relative ratios of carbon, hydrogen, and oxygen in organic compounds.
- The mass of carbon in the starting material is determined by a 1:1 ratio with the mass of carbon dioxide produced (as in the combustion reaction for methane already displayed).
- The initial hydrogen mass is determined by a 2:1 ratio with the amount of water produced.
- The data and the ratios can then be used to calculate the empirical formula of the unknown sample.
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- In a balanced chemical equation, we can easily determine the stoichiometric ratio between the number of moles of reactants and the number of moles of products, because this ratio will always be a positive integer ratio.
- Therefore, the stoichiometric ratio, oftentimes referred to simply as the "mole ratio" or "molar ratio," between N2(g), H2(g), and NH3(g) is 1:3:2.
- In the equation H2(g) + Cl2(g) → 2 HCl(g), what is the molar ratio (stoichiometric ratio) between H2(g) and HCl(g)?
- The molar ratio between these two compounds is therefore 1:2.
- What is the simplest ratio of hydrogen to chlorine for forming hydrogen chloride?
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- Mass spectrometry is a powerful characterization method that identifies elements, isotopes, and compounds based on mass-to-charge ratios.
- Mass spectrometers separate compounds based on a property known as the mass-to-charge ratio: the mass of the atom divided by its charge.
- Mass analyzers separate the ions according to their mass-to-charge ratios.
- Depending on the applied voltage, only ions of a certain mass-to-charge ratio will pass through the analyzer.
- They are separated according to their mass-to-charge ratios.