Newest questions and responses by Janaiby
  1. chemistry

    If a 8.6195 g of a mixture which contains (20.0 % of CuSO4.XH2O and 80.0 % of sand) was heated in a crucible then cooled in the desiccator the mass obtained was 7.9976 g. a- Find X the number of water of hydration in the Hydrate (CuSO4.XH2O) (MM of CuSO4 =

    asked on July 15, 2013
  2. chemistry

    A thermometer scale is calibrated (marked off) in a degree Celsius from 1 oC to 50 oC. Determine how many significant figures should be used to express the outdoor temperature if the temperature is more than 1 oC and less than 10 oC: (A) 1 (B) 2 (C) 3 (D)

    asked on July 15, 2013
  3. chemistry

    When 85.0 g of CH4 are mixed with 160. g of O2 the limiting reactant is __________. CH4 + 2O2 ¨ CO2 + 2H2O A) CH4 B) O2 C) CO2 D) H2O

    asked on July 13, 2013
  4. chemistry

    When 3.05 moles of CH4 are mixed with 5.03 moles of O2 the limiting reactant is __________. CH4 + 2O2 ¨ CO2 + 2H2O A) CH4 B) O2 C) CO2 D) H2O

    asked on July 13, 2013
  5. chemistry

    A 0.0677 g sample of magnesium metal reacted with excess hydrochloric acid solution to produce 69.9 mL of hydrogen gas. The gas was collected over water at 21.0° C. The levels of water inside and outside the gas collecting tube are identical (meaning that

    asked on July 8, 2013
  6. physics

    A brick weight 17.8N and is resting on the ground. Its dimensions are 0.203mx0.089mx0.0570m. A number of the bricks are then stacked on top of this one. What is the smallest number of whole bricks (including the one on the ground) that could be used, so

    asked on May 28, 2013
  7. physics

    - A copper cylinder is initially at 20.0oC. At what temperature will its volume be 0.15% larger than it is at 20.0oC? Take: ƒÒcofficient of thermal expansion of volume for cu= 5.1x10-5 /C

    asked on May 28, 2013
  8. Physics

    A substance is heated from –12.0oF to 150.0oF. What is its change in temperature on (a) the Celsius scales,(b) the Kelvin scales

    asked on May 28, 2013
  9. physics

    A steel beam is used in the construction of a skyscraper. By what fraction īL/Lo does the length of the beam increase when the temperature changes from that on a cold winter day (-15.0oF) to that on a summer day (+105.0oF)? Take: Ąsteel= 12x10-6/Co

    asked on May 28, 2013
  10. physical science

    On a new temperature scale the steam point is 348 °X, and the ice point is 112 °X. What is the temperature on this scale that corresponds to 28.0 °C?

    asked on May 23, 2013
  11. Physics

    - The Mariana trench is located in the Pacific Ocean at a depth of about 11000 m below the surface of the water. The density of seawater is 1025 kg/m3. (a) If an underwater vehicle were to explore such a depth, what forces would the water exert on the

    asked on May 13, 2013
  12. Physical Education

    (a) Calculate the average blood velocity in the major arties given that the aorta has a radius of 1.0 cm, the blood velocity is 30 cm/s in the aorta, and the total cross-sectional area of the major arties is 20 cm2 (b) What is the total flow rate? (c) On

    asked on May 13, 2013
  13. Physical Science

    Blood is pumped from the heart at a rate of 5L/min into the aorta of radius 2.0cm. Assuming that the density of blood 1x103 kg/m3 .Determine the velocity of blood through the aorta

    asked on May 13, 2013
  14. Physical Science

    A dentist’s chair with a patient in it weight 2100N. The output plunger of a hydraulic system begins to lift the chair, when the dentist’s foot applies of 55N to the input piston. Neglect any height difference between the plunder and the piston. What

    asked on May 13, 2013
  15. Physical Education

    Suppose that blood flows through the aorta with a speed of 0.35 m/s. The cross-sectional area of the aorta is 2.0x10-4 m2. (a) Find the volume flow rate of the blood (b) The aorta branches into tens of thousands of capillaries whose total cross-sectional

    asked on May 13, 2013
  16. Physical Education

    A solid object floats on ethyl alcohol, with 68.2%of the object’s volume submerged .Find the density of the object. Take density of alcohol =806 kg/m

    asked on May 13, 2013
  17. physical

    A solid cylinder has a radius of 0.051 m and a height of 0.0030. The cylinder is composed of two different materials with mass densites of 1950 kg/m3. If each of the two materials occupies an equal volume, what is the mass of the cylinder?

    asked on May 10, 2013
  1. chemistry

    please help me ,becauce i have final exam tomorrow

    posted on July 15, 2013
  2. physics

    Thank you ^__^

    posted on May 28, 2013
  3. Physical Education

    Thank you very much ^__^

    posted on May 13, 2013
  4. Physical Education

    Oh ,,I am sorry , I mean science

    posted on May 13, 2013
  5. Physical Education

    math ..

    posted on May 13, 2013