• What is 2/3 of water plus 2/3 of water?

    7 answers · 4 days ago
  • What is the name of the compound CrPO4 • 5H2O?

    What is the name of the compound CrPO4 • 5H2O?
    What is the name of the compound CrPO4 • 5H2O?
    4 answers · 3 days ago
  • Is it really true that any thing that has mass have atoms inside them??

    does table & chairs also have atoms???
    does table & chairs also have atoms???
    8 answers · 6 days ago
  • 116.6 g of magnesium hydroxide is allowed to react with 500 mL of 2M HCl. What is the maximum amount of magnesium chloride that can be...?

    Best answer: Start with the balanced equation: Mg(OH)₂ + 2HCl → MgCl₂ + 2H₂O Next, calculate moles of Mg(OH)₂ using molar mass: 116.6 g Mg(OH)₂ * (1 mol Mg(OH)₂ / 58.3 g Mg(OH)₂) = 2 mol Mg(OH)₂ Then, calculate the moles of HCl given the volume and concentration: 2 mol/L * 0.500 L = 1 mol HCl Now you need to find the... show more
    Best answer: Start with the balanced equation:
    Mg(OH)₂ + 2HCl → MgCl₂ + 2H₂O

    Next, calculate moles of Mg(OH)₂ using molar mass:
    116.6 g Mg(OH)₂ * (1 mol Mg(OH)₂ / 58.3 g Mg(OH)₂) = 2 mol Mg(OH)₂

    Then, calculate the moles of HCl given the volume and concentration:
    2 mol/L * 0.500 L = 1 mol HCl

    Now you need to find the limiting reactant. From the balanced equation, we see that 1 mol of Mg(OH)₂ reacts with 2 mol of HCl. Therefore, 2 mol of Mg(OH)₂ reacts with 4 mol of HCl. But we only have 1 mol of HCl. So that's the limiting reactant, and will determine how much product can be produced.

    Using stoichiometry:
    1 mol HCl * (1 mol MgCl₂ / 2 mol HCl) = 0.5 mol MgCl₂
    0.5 mol MgCl₂ * (95.2 g MgCl₂ / mol MgCl₂) = 47.6 g MgCl₂

    The closest answer is b.
    4 answers · 4 days ago
  • How do I separate a mixture of gravel and raisins w/o using mechanical means?

    Without sorting the mixture by hand or other mechanical means, describe a method to separate a mixture of raisins and pea-gravel (small rocks with the same coloring and size as the raisins). I thought of adding water to separate the mixture, but then it came to my realization that both gravel and raisins sink in... show more
    Without sorting the mixture by hand or other mechanical means, describe a method to separate a mixture of raisins and pea-gravel (small rocks with the same coloring and size as the raisins). I thought of adding water to separate the mixture, but then it came to my realization that both gravel and raisins sink in water...
    5 answers · 5 days ago
  • Will carbon dioxide develop in my confined drawer?

    Best answer: No, it is not very likely. Drawers aren't exactly air-sealed anyway even if there was generation of carbon dioxide so no build-up of hazardous gas is probably, and really, even if the drawer was sealed perfectly and filled with carbon dioxide, it still likely would not be a source of a problem unless you were... show more
    Best answer: No, it is not very likely. Drawers aren't exactly air-sealed anyway even if there was generation of carbon dioxide so no build-up of hazardous gas is probably, and really, even if the drawer was sealed perfectly and filled with carbon dioxide, it still likely would not be a source of a problem unless you were in a very small room or closet that was equally poorly ventilated. A musty odor and perhaps allergy to dust is about the worst you will experience unless you have some really weird chemicals stored in there.
    5 answers · 6 days ago
  • Is water wet?

    7 answers · 1 week ago
  • So is bronze a metal or non-metal? Help?

    11 answers · 2 weeks ago
  • LD50 Meaning?

    Best answer: LD50 = Lethal Dosage resulting in 50% death rate of a population. ********** That population can be anything. mice, dogs, rabbits, even people. The population is ALWAYS specified. So is the method of dosing. example .. LD50 oral rats sodium chloride = 3000 mg/kg .. LD50 oral mice sodium chloride = 4000... show more
    Best answer: LD50 = Lethal Dosage resulting in 50% death rate of a population.

    **********
    That population can be anything. mice, dogs, rabbits, even people. The population is ALWAYS specified. So is the method of dosing.

    example
    .. LD50 oral rats sodium chloride = 3000 mg/kg
    .. LD50 oral mice sodium chloride = 4000 mg/kg

    that means that for a large group of rats, 50% will die after oral ingestion of 3000mg NaCl / 1kg body weight
    and it means for a large group of mice, 50% will die after oral ingestion of 4000mg NaCl / 1kg body weight

    and we can say..
    .. LD50 oral humans is unknown (because we didn't test NaCl on humans) but shouldn't be
    .. too different from that of rats or mice.
    4 answers · 7 days ago
  • When the characteristics or state (solid, liquid or gas) of a substance change but the chemical composition does not change it indicates?

    Best answer: Changes in state..... The usual answer for the type of change associated with changes in phase is "physical change." The common assumption is that in a phase change, there is no change in the chemical composition of the substance. That is true, up to a point. This is what makes phase changes sit on... show more
    Best answer: Changes in state.....

    The usual answer for the type of change associated with changes in phase is "physical change." The common assumption is that in a phase change, there is no change in the chemical composition of the substance. That is true, up to a point. This is what makes phase changes sit on the fence between physical and chemical changes.

    Consider good old table salt, NaCl. It is a solid at room temperature and 1 atm of pressure, and it is a network solid consisting of alternating Na and Cl atoms. It is an electrical insulator. But when the solid is in the molten state it exists as free Na+ ions and Cl- ions which are no longer bound in a lattice. Bonds have been broken and ions formed. In addition, the molten sodium chloride is now an excellent conductor of electricity. Passing electricity through the molten material will produce sodium metal and chlorine gas. Since solid sodium chloride is a nonconductor and a rigid network, it will not form molten sodium metal and chlorine gas when electricity is applied.

    The bottom line is that sodium chloride has vastly different physical and chemical properties as a result of a phase change which puts it on the fence between a physical change and a chemical change.

    This and other reasons are why I would suggest to textbook authors to avoid any mention of physical and chemical changes or properties which are typically in the first or second chapter, at least until the student has acquired enough background to understand the nuanced differences between the two.
    4 answers · 1 week ago
  • Help Please?

    If you put 3.27 moles of an ideal gas in a 50.0 L tanks at 35.0C, what pressure will it create? (Unit=Pa)
    If you put 3.27 moles of an ideal gas in a 50.0 L tanks at 35.0C, what pressure will it create? (Unit=Pa)
    5 answers · 1 week ago
  • Help please!!!?

    Best answer: In this problem, the heat energy that is absorbed by the block is equal to the heat energy that is released by the water. According to a table in my physics book, the specific heat of water is 4,186 J/(kg * ˚C) For the water, Q = 0.217 * 4,186 * (25 – 16.4) = 7,811.9132 J For the block, Q = 0350 * x * (16.4 –... show more
    Best answer: In this problem, the heat energy that is absorbed by the block is equal to the heat energy that is released by the water. According to a table in my physics book, the specific heat of water is 4,186 J/(kg * ˚C)

    For the water, Q = 0.217 * 4,186 * (25 – 16.4) = 7,811.9132 J
    For the block, Q = 0350 * x * (16.4 – -27.5) = 15.365 * x
    15.365 * x = 7,811.9132
    x = 7,811.9132 ÷ 15.635

    The specific heat of the block is approximately 508 J/(kg * ˚C).
    5 answers · 2 weeks ago
  • Alka Seltzer chemistry question.?

    Best answer: Alka-Seltzer.... Aspirin is usually the sodium salt of acetylsalicylic acid, which is soluble in water. The citric acid and sodium bicarbonate need to dissolve in water before they can react. NaHCO3(s) --H2O--> Na+ + HCO3^- C3H5O(COOH)3(s) --H2O--> C3H5O(COOH)3(aq) ................. citric acid is a weak... show more
    Best answer: Alka-Seltzer....

    Aspirin is usually the sodium salt of acetylsalicylic acid, which is soluble in water. The citric acid and sodium bicarbonate need to dissolve in water before they can react.
    NaHCO3(s) --H2O--> Na+ + HCO3^-
    C3H5O(COOH)3(s) --H2O--> C3H5O(COOH)3(aq) ................. citric acid is a weak acid

    Carbonates and bicarbonates react with acids to liberate CO2 gas. There is an excess of bicarbonate in the mixture which, when drunk, reacts with the acid in the stomach.

    3HCO3^- + C3H5O(COOH)3(aq) --> C3H5(COO)3^3- + 3CO2(g) + 3H2O(l) ..... The fiz you see and hear
    HCO3^- + H+ --> CO2(g) + H2O(l) ............. bicarbonate neutralizes acid in the stomach
    3 answers · 1 week ago