annabel

Most popular questions and responses by annabel
  1. Chemistry

    a mixture of 4.00 moles of hydrogen and 3.00 moles of oxygen is ignited, forming water. what is the maximum amount of water in grams that can be formed?

    asked on May 16, 2012
  2. Chemistry

    A solution contains 1.50 g of dissolved Pb 2+ ions. How many grams of NaI must be added to the solution to completely precipitate all of the dissolved Pb 2+ as PbI2?

    asked on April 24, 2012
  3. Chemistry

    How many moles of O2 are needed for the complete combustion of 3 moles of CH4?

    asked on April 24, 2012
  4. Math

    Anita says the plus sign + forms 2 pairs of vetical angles. Charles says it forms 2 pairs of congruent angles? Who is correct, and why? Wouldn't it be both, because there are 2 pairs of opposite angles with the same measure, and 4 congruent angles.

    asked on March 1, 2011
  5. Chemistry

    how do I work out the molecular mass of a substance such as oxide of arsenic? If I'm trying to work out the oxide part of this problem, where does hydrogen come into it? You have to know the mass, and how many moles. There are other methods. Hydrogen?

    asked on February 2, 2007
  6. Chemistry

    if the yieeld for the following reaction is 85% how many grams of Al2S3 should be used to produce 165 g of Al(OH)3? Al2S3+6H2O-->2Al(OH)3+3H2S

    asked on May 16, 2012
  7. Chemistry

    A 1.8 mole sample of a compound weighs 195 g and is found to be 11.18% H and 88.82% C. What is the molecular formula for the compound?

    asked on April 24, 2012
  8. Chemistry

    I need to work out the density of the gaseous oxide of arsenic at STP in g L-1 I realise density = mass/volume but my answer works out very high!! I have already worked out the volume to be 52cm^3 (Cubed). the mass to start with was 0.702g and at the end

    asked on January 31, 2007
  9. Chemistry

    A sample of iron ore contains 1.02 x 10^24 Fe atoms and is found to be 69.94% Fe by mass. What is the mass of the sample?

    asked on April 24, 2012
  10. math

    Wayne will get $4200 if his salary is increase by 20%.Wayne's salary is 40% less the barry.Find Barry's salary.

    asked on April 28, 2013
  11. math

    Wayne will get $4200 if his salary is increase by 20%.Wayne's salary is 40% less the barry.Find Barry's salary.

    asked on April 28, 2013
  12. Chemistry

    How many atoms are there in a 15.0-g sample of KBr?

    asked on April 23, 2012
  13. Chemistry

    How many atoms are there in a 15.0-g sample of KBr?

    asked on April 23, 2012
  14. Writing

    Complete the phrase: You give me love, You gave me life. You give me shelter, You gave me __________.

    asked on March 7, 2011
  1. Math algebra

    If you have 6 cups of flour for pancakes and you have 2 cups of water

    posted on September 11, 2016
  2. life orientation

    by introducing campaign like NGO

    posted on April 27, 2016
  3. chemistry

    sorry convert your 53 grams to kg. because your specific heat capacity is in J per kg this should change your answer

    posted on April 24, 2012
  4. chemistry

    q=m*c*change of t m=mass c= specific heat change of t= final temp- initial temp fill in these with your numbers and you should get the answer

    posted on April 24, 2012
  5. Math

    PLEASE HELP!!!!!

    posted on March 1, 2011
  6. english

    Harder to use because you have to make everything balance well, or it will throw it off.

    posted on March 1, 2011
  7. english

    I think they are harder because you don't have entire control over the string puppet, like wind can move it, and the strings can get tangled up.

    posted on March 1, 2011