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CHEM HELP NEEDED?

Out of the following, a 32g sample of oxygen, O2, gas is equal to:?

Which of the following contains the least number of atoms?

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need some help please?

please explain this to me?

Chemistry HW question help!?

What is the edge length of a face-centered cubic unit cell made up of atoms having a radius of 139 pm?

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I need help for this one. explain if you could thank you?

what is the molecular geometry surrounding the nitrogen atom in nf3?

Why can not a tertiary alkyl halide be used in the reaction of making an amine from an alkyl halide with azide?

Is benzamide polar or non polar?

need help on physics?

this reaction in house temperature happend: 2SO3----->2SO2+O2 :delta(H)=+19.8 Is delta(G) negative? Why?

Please help?

Trigonometry help?

what is the molarity (moles per liter) of a solution prepared by dissolving 320.g of NaOH [molar mass 40.0g/mol] in enough water to =800ml?

What is [H3O+] for a buffer solution that is 0.200 M in acid and 0.500 M in the corresponding salt, if the weak acid's Ka = 5.50 × 10−7?

solubility product of AgCl is 1.77 * (10^ -9) in 25 degrees C. Calculate the solubility of Ag+ ion in 0.1M NaCl solution!?

chemistry redox reaction help?

Balancing Redox acid?

Need help with limiting reactant problems in chemistry?

What is the pH of an aqueous solution of 2.09×10-3 M hydroiodic acid?

A generic salt, AB2, has a molar mass of 249 g/mol and a solubility of 1.10 g/L at 25 °C. What is the Ksp of this salt at 25 °C?

Determine the number of moles present in 8.39 x 1024 molecules of fluorine gas (F2)?

Suppose 1.25 g of sodium peroxide is added to a large excess of water. What mass of oxygen gas will be produced?

Identify the number of electron groups around a molecule with a tetrahedral shape.?

A gas fire with a yellow coloured flame is dangerous because ..?

chemistry back titration question?

AS LEVEL CHEMISTRY please help . I have an answer to my question but I don't know if its correct?

Chemistry Density Question (Any help appreciated, thanks!)?

AP Chemistry pH buffer question?? Help!?

The empirical formula of a compound is NO2. Its molecular mass is 46amu. What is the molecular formula of the compound?

How long would it take (min) for argon-44 to decrease from 96.0 to 12.0mg? Ar-44 Pb-196 K-44 Indium-117?

Chemistry help!!?

Chemistry help!?

PLEASE HELP...STUCK WITH THIS PORTION?

PLEASE HELP...STUCK ON THIS PORTION?

STUCK ON THESE TWO AS WELL?

Silicon metal (Si) reacts with nitrogen gas (N2) to give silicon nitride (Si3N4) based on the following balanced reaction: 3 Si + 2 N2 -->?

A certain isotope decays from 80 grams to 2.5 grams in 34 days. What is the half life of this isotope?

mastering chem?

mastering chemistry?

CHEMISTRY?

Calculate the wavelength (in nanometers) of a H atom (mass = 1.674 × 10−27 kg) moving at 3.75 × 102 cm/s.?

Redox Reaction Balanced Equation?

What is the de Broglie wavelength, in cm, of a 12.4−g hummingbird flying at 1.20 × 102 mph? (1 mile = 1.61 km.)?

Indicate the total number of: (a) p electrons in N (Z = 7) (b) s electrons in Si (Z = 14) (c) 3d electrons in S (Z = 16)?