Chemistry

Start Free Trial

Chemistry Questions and Answers

What are some examples of homogeneous mixtures and heterogeneous mixtures?

What is the formula for converting grams to atoms or atoms to grams? How many atoms are in 878g of fluorine?

Is CO2 + H2O ->H2CO3 an oxidation-reduction reaction?

If you know only the number of neutrons can you determine what the element is?

To determine the mass percentage of barium in a 2.016 g sample, a titration is conducted: If the sample is titrated with 20 mL of 0.20M H2SO4 and that produces a BaSO4 precipitate. a) how many moles of BaSO4 were found in the titration? b) what was the mass of barium present in the original sample? c) what was the mass percent of barium in the original sample?

A sample containing 0.175g of Cl- is dissolved in 50 mL of deionized H2O. The solution is titrated to the equivalence point with a AgNO3 solution. The final volume of the titrated sample is 75 mL. a. What is the concentration of the AgNO3 solution? b. How many grams of AgCl are precipitated?

What are some examples of compounds?

an unknown solution sample weighing 0.2583g is titrated to the end point with 47.28mL of a 0.10M AgNO3 solution. (question underneath) what is the weight percent of Cl- in the sample?

How are atoms of different elements different?

How many milliliters of water would you add to 100 mL of 1.0M HCL to prepare a final solution of 0.25 M HCL?

What holds atoms together in ionic bonds?

Write the symbol for a cation and an anion that are isoelectronic with Krypton. Is it possible for a cation to be isoelectronic with an anion from the same period? Explain.

what functional group is present in the following compound H2N-CH2-CH2-CH2-O-CH2-COO-CH3?

Why do the elements of the same group have similar properties ?

What is the purpose of Chromatography? objective,what is the purpose doing lab experiment for Chromatography?

What does the red glow indicate in the following experiment: A student heated a mixture of iron filings & sulfur strongly. He saw a red glow spread through the mixture as the reaction continued. At the end of the experiment a black solid had been formed.

What is the concentration of a solution that has a volume of 2.5 L and contains 660 grams of calcium phosphate?

What molecular compound is formed by Phosphorus and Fluorine?

Calculate the percent composition of C14H9Cl5 (DDT).

What is the oxidation number of sulfate?

What mass of carbon monoxide and carbon dioxide produced when a 5.00 g sample of pure carbon is burnt under the following conditions: When elemental carbon is burned in the open atmosphere with plenty of oxygen gas present, the product is carbon dioxide. C+O2 -->CO2 However, when the amount of oxygen present during the burning of the carbon is restricted, carbon monoxide is more likely to result 2C + O2 --->2CO

Aluminum reacts with oxygen in the following chemical reaction:  Al + O2 → Al2O3. How many moles of Al2O3 are formed from the reaction of 6.38 mol O2 and 9.15 mol of Al?

An alloy contains copper and zinc. Some of the zinc has become oxidized to zinc oxide. What is the result of adding an excess of dilute sulfuric acid to the alloy? 1. A blue solution and a white solid remains. 2. A colorless solution and a pink / brown solid remains. 3. The alloy dissolves completely to give a blue solution. 4. The alloy dissolves completely to give a colorless solution.

If we use 3.00g of CuCl2 dihydrate, what mass of aluminum is required to complete the reaction? Here is the balanced chemical equation: 3CuCl2 dihydrate + 2Al produces 3Cu + 2AlCl3 + 6H2O Full explanation please!!

What is the pH when 100ml of 0.1 M NaOH is added to 150ml of 0.2 M HAc if pKa for acetic acid is 4.76?

Vanadium (V) oxide is used as catalyst in the reaction below.2 SO2 (g) + O2 (g) --->  2 SO3 (g) Explain how Vanadium (V) oxide is able to reduce activation energy and to increase the rate of the reaction.

Name the following compounds: AgNO3, K2S, BaS, Agl & Kl

Why can copper sulfate dissolve in water easily?

Balance the chemical equation: K4Fe(CN)6 + H2SO4 + H2O = K2SO4 + FeSO4 + (NH4)2SO4 + CO.

What is the concentration of hydrogen ions in 0.05 mole/dm^3 sulfuric acid? A) 0.025 g/dm^3 B) 0.05 g/dm^3 C) 0.10 g/dm^3 D) 2.0 g/dm^3

If the atomic number of chromium is 24 and the atomic mass is 52 what is the number of electrons, protons and neutrons in chromium.

How to read chemical formulas? I know the very basics - for instance, some simple formulas are just spelled, but what about something more complicated? For instance, how do you read Mg(OH)2 ? I know, what a compund it is, I need some general reading rules only. Thanks beforehand!

Determine the empirical formula of an oxide of silicon from the following: Mass of crucible = 18.20 g, mass of crucible + silicon = 18.48 g and mass of crucible + oxide of silicon = 18.80 g.

A 0.0560-g sample of acetic acid is added to enough water to make 50.00 mL of solution. How do you calculate [H], [CH3COO-], [CH3COOH] and the pH? The pH is at equilibrium and Ka for acetic acid is 1.8x10^-5

What is the concentration of nitrogen atoms in this solution? A typical solid fertiliser for use with household plants and shrubs contains the elements N,P, and K in the ratio of 15g: 30g: 15g per 100g of fertiliser. The recommended usage of fertiliser is 14g of fertiliser per 5dm^3 of water. What is the concentration of nitrogen atoms in this solution? [Relative atomic masses of N, P and K are 14.0, 31.0, 39.1 respectively]

How is fission different from alpha or beta decay?

Thyroxine is a hormone secreted by the thyroid gland and has a formula of C15H11NO4I4. How many grams of iodine are there in a 5g sample of thyroxine?

Which law would be used to compare the mass of oxygen in CO and CO2? Explain in terms of law of definte proportions or the law of Multiple Proportions.

An element has mass number 13 and 7 neutrons. What is it an isotope of?

How are gasoline and fat chemically similar? In spite of these chemical similarities, how are they different in their chemical properties?

How many grams of ammonium sulfate are needed to make a 0.25 L solution at a concentration of 6 M?

Given 4K(s) + O2(g) ---> 2K2O(s), how many grams of K2O(s) can be produced if 3.91 grams of K(s) are allowed to react with 1.60 grams of O2(g)?

What is the concentration of a 450 mL solution that contains 200 grams of iron (II) chloride?

What is the formula name for Ca2+ and NH4+?

What is the difference between biochemical, pharmaceutical, and diagnostic chemical reactions in healthcare? What is a specific example that exists for each of these chemical reaction types above and why might it be of importance to healthcare professionals? Please provide reference links if you can.

What is the concentration of a solution with a volume of 9 mL that contains 2 grams of iron (III) hydroxide?

How could I separate a mixture of salt and sugar?

How many moles of H2SO4 will react with 18 mol of Al in a chemical reaction involving the two.

Which is more stable: the Sodium ion or the Sodium atom?

Compare dehydration synthesis and hydrolysis reaction.