Science Homework Help

Why is the sun important in our lives?

Posted by dd711 May 15, 2013 at 4:02 PM via iOS. 1 educator answer. »

In the equilibrium 2SO_3 (g) + heat <---> 2SO_2 (g) +O_2 (g)  predict qualitatively the effect of increasing the total pressure and...

Posted by spock4 May 15, 2013 at 3:59 PM via web. 1 educator answer. »

Calculate the number of moles of oxygen in 2.00L at 24 degrees Celsius and 750 torr.

Posted by bella-80085 May 15, 2013 at 3:43 PM via web. 1 educator answer. »

 Which of the following statements is evidence for the existence of ions in ioniccompounds?A Ionic compounds, in the solid state, conduct...

Posted by roshan-rox May 15, 2013 at 3:43 PM via web. 1 educator answer. »

Metals are good conductors of electricity because A metal atoms are arranged in a regular lattice. B metal ions are very close to each other....

Posted by roshan-rox May 15, 2013 at 3:42 PM via web. 1 educator answer. »

When an Al^4+ ion is formed from an Al atom, the fourth electron is lost from theA 1s sub-shell. B 2s sub-shell. C 2p sub-shell. D 3s sub-shell.

Posted by roshan-rox May 15, 2013 at 3:41 PM via web. 1 educator answer. »

What volume of CO2 (g) measured at STP, can be obtained by the reaction of 68.0 g CaCo3 with excess hydrochloric acid? CaCO3 (s) + 2HCl (aq)...

Posted by bella-80085 May 15, 2013 at 3:39 PM via web. 1 educator answer. »

In an experiment to measure the enthalpy change of a reaction involving gases,which of the following conditions must always be kept...

Posted by roshan-rox May 15, 2013 at 3:39 PM via web. 1 educator answer. »

How many molecules are present in 16 g of oxygen gas, O2(g)?[Avogadro constant = 6 × 10^23 mol^−1]A)  96 × 10^23 B ) 12 × 10^23 C ) 6 ×...

Posted by roshan-rox May 15, 2013 at 3:37 PM via web. 1 educator answer. »

What is the volume of 2.0 moles of oxygen collected over water at 23 degrees Celsius and 798 torr? (at 23 degrees Celsius, the vapor pressure...

Posted by bella-80085 May 15, 2013 at 3:32 PM via web. 1 educator answer. »

Why does tree bark swell up when it is cut?

Posted by user9145827 May 15, 2013 at 12:52 PM via web. Be the first to answer. »

What is the difference between weak and strong acids?

Posted by homework-help May 15, 2013 at 11:46 AM via web. 1 educator answer. »

CsCl dissolves in water according to the equation: CsCl (aq) <---> Cs^+ (aq) + Cl^- (aq) A 0.121 m solution of CsCl freezes at -0.403...

Posted by spock3 May 15, 2013 at 11:00 AM via web. 1 educator answer. »

A dilute aqueous solution (0.250 L) of an organic compund soluble in water is formed by dissolving 22.3 g of the organic compound in water....

Posted by spock2 May 15, 2013 at 10:54 AM via web. 1 educator answer. »

A solution of 0.64 g of adrenaline in 36.0 g of CCl_4 (K_b = 5.02 degrees celcius/m) causes an elevation of 0.49 degrees celcius in the...

Posted by spock1 May 15, 2013 at 10:50 AM via web. 1 educator answer. »

Evaluate the uses of waves in our world, suggesting improvements to their real life application.

Posted by jasma82 May 15, 2013 at 5:52 AM via web. 1 educator answer. »

What thing makes up our body the most?

Posted by terrence958 May 15, 2013 at 3:30 AM via web. 2 educator answers. »

What is the name of a large protist that has cilia around its mouth to sweep in food

Posted by audreyjms May 15, 2013 at 2:00 AM via web. Be the first to answer. »

patients generally recover from acute hepatitis, while they show no symptoms but still carry the virus and can pass it toothers. During this...

Posted by candyland28 May 14, 2013 at 9:46 PM via web. Be the first to answer. »

How does the government limit the effect of environmental damage?  Also, How does the government worsen the effect of environmental...

Posted by pinkyheart99 May 14, 2013 at 6:49 PM via web. 1 educator answer. »

An isotope of an element, atomic number z, has mass number 2z + 4. How manyneutrons are in the nucleus of the element?A) z + 4 B) z + 2 C) z D) 4

Posted by roshan-rox May 14, 2013 at 2:38 PM via web. 1 educator answer. »

Which of the following processes has the highest atom economy?A) Making poly(ethene) from ethene.B) Making ethene from eicosane, C20H42.C)...

Posted by roshan-rox May 14, 2013 at 2:35 PM via web. 1 educator answer. »

Write any four features of a non ideal gas.

Posted by shanezehra May 14, 2013 at 12:08 PM via web. 1 educator answer. »

a. Is it true to consider ‘torque’ as a ‘force’? Give its explanation. b. A torque that causes counterclockwise acceleration is a...

Posted by sultanbaloch May 14, 2013 at 5:53 AM via web. 1 educator answer. »

I have a baseball bat. I shave off some weight from the handle and put it on the head of the bat. Abaseball player thinks I have changed the...

Posted by bc090400375 May 14, 2013 at 5:50 AM via web. 1 educator answer. »

what are the basic parts of cells and what are their function, and what's cell theory (may I say I'm only 11 so nothing to confusing) thanks!!

Posted by anniecoughlin May 14, 2013 at 2:01 AM via iOS. 1 educator answer. »

If I pinch hold a book, with 6N on either side why is there only one force, of 6 newton on the free body diagram?   for example, the book has...

Posted by user2963919 May 14, 2013 at 1:28 AM via web. Be the first to answer. »

Why do some lightning bugs stay in the pupa stage as a glow worm?

Posted by ruthemmacharlie May 13, 2013 at 7:09 PM via iOS. Be the first to answer. »

Two converging lenses, with focal length f1=20cm and f2=30cm, are placed 90cm apart. An object of the height 5 cm is placed 50 cm in front of...

Posted by computergeek21 May 13, 2013 at 6:21 PM via web. 1 educator answer. »

research about any one atom ( I chose Hydrogen) Answer the following A description of a process in the human body that is impacted by the atom...

Posted by msjohnson718 May 13, 2013 at 5:22 PM via web. 1 educator answer. »

Can you please give me an answer to what is a capacitor, and what is dielectric? [This question was edited because only one question (plus one...

Posted by lilian-0716 May 13, 2013 at 12:11 PM via web. 1 educator answer. »

What is the difference between compounds, molecules and mixtures?

Posted by taylor-winston May 13, 2013 at 8:36 AM via iOS. 1 educator answer. »

I find an answer by asking Google "Why does atomic radius decrease across a period?" And here's the answer : Atomic radius decreases because...

Posted by mattlimey May 13, 2013 at 8:23 AM via web. 2 educator answers. »

1. All current commercial power plants use the process of fission to produce electricity. What would be the GREATEST benefit of switching to...

Posted by caveman111 May 13, 2013 at 3:35 AM via web. 1 educator answer. »

A radio wave, sent from Mars to the Earth when the two are cloest each other, takes 3.03 minutes. Another radio wave, sent from Mars to the...

Posted by andrewmezzo May 13, 2013 at 2:00 AM via web. 1 educator answer. »

Explain where the electron comes from and how it gains energy during the light reactions.  Describe how the energy in the electron is used to...

Posted by msmith11003 May 13, 2013 at 12:56 AM via web. 1 educator answer. »

Two converging lenses, with focal length f1=20cm and f2=30cm, are placed 90cm apart. An object of the height 5 cm is placed 50 cm in front of...

Posted by ceeee May 13, 2013 at 12:36 AM via web. 1 educator answer. »

How does an expermiment of flipping a coins from two times to 170 times relate to studying allele frequencies in population? 

Posted by sasuke24 May 12, 2013 at 11:31 PM via web. Be the first to answer. »

Have a beam of uniform strength the same cross-section throughout the beam? Explain  

Posted by uoor May 12, 2013 at 5:08 PM via web. Be the first to answer. »

What is a beam supported at its both ends?

Posted by markll May 12, 2013 at 5:05 PM via web. 1 educator answer. »

What is the stress induced by steel bar of 10 mm heated from 10° C to 30° C which is free to expand?  

Posted by mozostax May 12, 2013 at 4:19 PM via web. 1 educator answer. »

Is burning of a candle a combination of chemical and physical change?

Posted by wilfredmjeymar May 12, 2013 at 3:10 PM via web. 1 educator answer. »

a. Can you write the basic reason of resonance? Is there any role of natural frequency in thisphenomenon or not?b. Generally it is accepted...

Posted by bc090400375 May 12, 2013 at 3:07 PM via web. Be the first to answer. »

Why is enthalpy change of combustion reactants minus products when the enthalpy of formation is products minus reactants? Isn't one just a...

Posted by tuvshee May 12, 2013 at 2:07 PM via web. 1 educator answer. »

Would you puchase genetically modified seeds? why or why not? Give three reasons. As a farmer your corn crop has been affected for the past...

Posted by asmaspring May 12, 2013 at 12:40 PM via web. Be the first to answer. »

Genetically modified foods can have a negative impact on environment. Describe two situations where this is the case.

Posted by adilyas May 12, 2013 at 12:35 PM via web. Be the first to answer. »

Is it true or wrong that a point on a wheel rotates from 12 o’clock to 3 o’clock, so its angular displacement is 90 degrees? If yes...

Posted by sultanbaloch May 12, 2013 at 11:12 AM via web. 1 educator answer. »

Evaluate the results for negative ions to analyse the inorganic chemicals, considering how to improve subsequent experiments.

Posted by jasma82 May 12, 2013 at 8:06 AM via web. 1 educator answer. »

using point forms explain plants genetically modified using Agrobacterium tumefaciens? animals genetically modified using DNA microinjection  

Posted by ninaesl May 12, 2013 at 2:33 AM via web. 1 educator answer. »

What is the difference between 'thermal capacity' and 'specific heat capacity'?

Posted by spsaroj May 12, 2013 at 2:28 AM via web. 1 educator answer. »