Science Questions and Answers

Science

According to the law of reflection of light, angle of incidence and angle of reflection are always equal. Angle of incidence is the angle made by the incident ray of light with a normal drawn to...

Latest answer posted February 13, 2016 3:50 am UTC

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Science

First, let's define the two terms. Fission is the breaking down of a heavy atom into smaller atoms and subatomic particles. Fusion is the binding together of two smaller atoms into a larger atom....

Latest answer posted January 26, 2013 5:13 pm UTC

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Science

Newton's Second Law of Motion deals with unbalanced forces; the acceleration of an object is related to the mass of the object and the force applied to it, or F=ma. Experiments done that involve...

Latest answer posted March 19, 2016 9:19 pm UTC

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Science

Normally we would assume that BeCl2 would be sp hybridized; the beryllium only has two electrons to share, and the chlorines each need only one, so this should demand a total of two bonds, which is...

Latest answer posted August 5, 2016 4:16 am UTC

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Science

A compound microscope has two sets of lenses, the eyepiece lens and the objective lens. The sample to be studied is kept in a slide that is placed on a flat platform referred to as a stage. The...

Latest answer posted September 24, 2014 3:25 am UTC

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Science

CO3^2- is called a carbonate ion. First we need to count the total number of valence electrons. We just add the valence electrons of each atoms involved. C = 4 O = 6 x 3 e = 2 ---> we add...

Latest answer posted November 2, 2012 12:22 pm UTC

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Science

Displacement is usually the method that is used to measure the volume of an irregularly shaped object. The object is simply submerged in a liquid and the volume of liquid that is displaced is...

Latest answer posted September 10, 2015 1:56 am UTC

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Science

Upstream and downstream processing developments are terms related to Bioprocessing, particularly in the context of pharmaceutical industry. Bioprocessing refers to production of desired products...

Latest answer posted August 14, 2015 12:46 pm UTC

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Science

The data is text tells that `R_1 =2*R` and `R_2=R` The equivalent resistance of the two resistors connected in series is `R_(eq) =R_1+R_2 =2R+R =3R` As Ohm law states the current is the same in...

Latest answer posted September 23, 2013 6:29 am UTC

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Science

The solid cube of silver, between the opposite faces of which we have to find the resistance, has a density of 10.5 g/cm^3 and a mass of 90 g. Now density is given by mass/ volume or volume is...

Latest answer posted December 25, 2010 3:00 pm UTC

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Science

Glycolysis is a metabolic pathway that converts glucose into pyruvate, a three-carbon species. It involves 10 steps, seven of which are reversible while the rest, irreversible. The following steps...

Latest answer posted May 9, 2013 3:25 am UTC

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Science

The volume of a rock will vary depending on the size of the rock. Since a rock is an irregularly shaped object, a good way to determine its volume is by using water displacement. When an object is...

Latest answer posted June 7, 2016 1:17 pm UTC

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Science

Carbon dioxide is made of one carbon atom that is sandwhiched in between two oxygen atoms. The carbon atom is in between each of the two oxygen atoms and there is a double bond between each...

Latest answer posted December 28, 2015 3:51 pm UTC

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Science

In addition to the first response, you should never eat in a chemistry lab simply because those are the rules. I have worked in many science labs and they all had stated "no food or drink...

Latest answer posted April 28, 2010 12:09 am UTC

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Science

Speed is equal to distance divided by time. Velocity is speed in a particular direction. For the purposes of your question, we can think of speed and velocity as being the same thing. Kinetic...

Latest answer posted April 1, 2016 5:50 pm UTC

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Science

This is an ionic bond. Magnesium, found in group 2, has 2 valence electrons and needs to release them to become stable. Sulfur, found in group 16, has 6 valence electrons and takes two from...

Latest answer posted October 29, 2011 7:27 am UTC

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Science

Heat transfer can take place through three different mechanisms: conduction, convection and radiation. In conduction, heat is transferred through direct contact between bodies. Since direct contact...

Latest answer posted May 14, 2016 2:57 pm UTC

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Science

The bond between K and Br in KBr is considered ionic. An electron is essentially transferred from K to Br, resulting in the formation of the ions K+ and Br-, which are then held together by...

Latest answer posted October 14, 2015 6:31 am UTC

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Science

Leonardo DaVinci, the famous Italian thinker and artist, is usually credited with discovering that sound moves in waves. He made this discovery around the year 1500. However, some accounts say...

Latest answer posted January 1, 2010 2:23 am UTC

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Science

A current of 200 mA is flowing through the lamp. One ampere is the current that flows through the lamp when one coulomb of charge passes in one second. The charge of an electron is 1.602*10^-19 C....

Latest answer posted June 1, 2013 6:00 am UTC

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Science

Formic acid is a weak acid having Ka value of `1.7xx10^-4` . Potassium formate is its salt with a strong base, potassium hydroxide. A weak acid and its salt constitute a buffer solution, the pH of...

Latest answer posted February 24, 2015 4:32 pm UTC

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Science

Elements in the same group are those that are in a single vertical line from top to bottom. They have the most in common between the two directions. They share the same number of electrons in...

Latest answer posted December 24, 2012 1:23 am UTC

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Science

I don't know what experiment you are doing with the KMnO4 but in general solutions of unknown concentration must be standardized prior to use to determine their exact concentration so that the...

Latest answer posted December 4, 2011 9:09 am UTC

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Science

When we mix sand and water, no reaction takes place. The sand simply settles down at the bottom of the water container. This is because sand is heavier than water and hence cannot float in water....

Latest answer posted March 18, 2016 9:19 am UTC

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Science

Examples of polar substances include: - Water (H2O) - Ammonia (NH3) - Hydrogen Sulfide (H2S) Examples of non-polar substances: - Methane (CH4) - Carbon dioxide (CO2) - Diatomic gases, such as...

Latest answer posted January 31, 2016 6:36 pm UTC

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Science

As with the extinction of any other species, loss of the gray wolf could have a significant effect on the food chain(s) and ecosystems of which it is a member. Think of how a drop of water creates...

Latest answer posted July 7, 2016 12:36 am UTC

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Science

PH is a scale to determine the acidity of solution. `PH = -log[H^+]` `[H^+] = 10^(-PH)` At 25C PH sacle runs to 1-14. When the temperature changes this scale can be changed. At high...

Latest answer posted August 31, 2012 7:08 am UTC

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Science

Bleach is a class of commonly used chemicals for bleaching out or removing the color (of stains from clothes) and as a disinfectant (in the kitchen or bathroom). Bleach is typically based on...

Latest answer posted December 30, 2015 6:17 am UTC

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Science

When a candle burns, there is both a physical and chemical reaction. The physical change is quite obvious and in fact, it can be seen. When the candle burns, the wax slowly melts and the candle...

Latest answer posted February 11, 2014 11:01 pm UTC

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Science

ENO is an antacid (manufactured by GSK) which contains a mixture of sodium bicarbonate (`NaHCO_3` ), citric acid (`H_3C_6H_5O_7` ) and sodium carbonate (`Na_2CO_3` ). Initially, citric acid is...

Latest answer posted April 10, 2013 4:59 am UTC

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Science

The process of osmosis is the movement of water through a selectively permeable membrane from an area of high concentration to an area of low concentration without the input of energy. If a living...

Latest answer posted May 14, 2016 2:29 pm UTC

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Science

Our Earth is divided into three zones according to the temperature and precipitation conditions: tropical, polar and temperate. Tropical climatic zone lies (generally) between 30 degree North and...

Latest answer posted December 25, 2015 6:00 am UTC

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Science

According to Sir Isaac Newtons third law of motion, "For every action force, there is an equal reaction force in the opposite direction." What this means is when you exert a force upon the wall,...

Latest answer posted December 3, 2015 12:01 am UTC

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Science

The expression Ka is defined as the acid ionization constant. It is the equilibrium constant for the dissociation of an acid into its resulting ions. As a result, it is basically a numerical...

Latest answer posted May 18, 2013 10:45 pm UTC

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Science

Any wave has three parameters, the velocity of the wave v, the frequency of the wave f and the wavelength w. These are related to each other by the relation v = w*f The red-light of the He-Ne laser...

Latest answer posted February 11, 2012 10:55 am UTC

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Science

An electronic excited state of an atom refers to any electronic state above the ground state, and there is not just one such state but many. Let us start by defining the electronic ground state,...

Latest answer posted February 11, 2018 1:46 pm UTC

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Science

Hello! Each strand of hair has some layers, with medulla be the innermost. It is a hollow tube inside a hair, and its role is unknown yet. It may be present or absent, and if it is present, it may...

Latest answer posted November 27, 2015 1:35 pm UTC

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Science

The statement that motion is relative is an important concept in physics. The meaning behind this statement is that the motion of an object is relative to either the frame of reference of the...

Latest answer posted February 15, 2016 6:22 pm UTC

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Science

Thevinin's theorem relies on simplifying a circuit such that you remove the element for which you are trying to analyze its current/voltage drop and determine the equivalent voltage and in-line...

Latest answer posted July 24, 2016 5:18 am UTC

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Science

The reaction between iron(III) oxide and aluminum produces aluminum oxide and iron. The chemical equation of the reaction is: `3Fe_3O_2 + 4Al -> 2Al_2O_3 + 6Fe` This reaction is known as a...

Latest answer posted November 5, 2013 5:48 am UTC

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Science

Photosynthesis is important, in fact essential, to all life for a number of reasons. First, it makes it possible for plants to survive. Since almost the entire food chain depends on plant matter...

Latest answer posted May 14, 2016 5:20 pm UTC

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Science

The various species involved in the reaction have the following chemical formulas: zinc carbonate: ZnCO3 nitric acid: HNO3 Zinc nitrate: Zn(NO3)2 water: H2O carbon dioxide: CO2 The chemical...

Latest answer posted May 4, 2016 5:39 am UTC

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Science

In simplest terms, weathering refers to breakdown of rocks. The process can be both natural and man-made. Here is a list of human activities that cause weathering of rocks: Burning of fossil fuels...

Latest answer posted August 12, 2015 12:30 am UTC

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Science

Cellular growth, development, and division is a process known as the cell cycle. The cell cycle is typically divided into three large phases. Those phases are interphase, mitosis, and cytokinesis....

Latest answer posted January 28, 2021 4:28 pm UTC

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Science

The xylem and phloem of plants are most similar to veins, arteries, and capillaries. In a plant, xylem are used to transport water, while the phloem are used to transport nutrients via sap. Xylem...

Latest answer posted June 2, 2016 3:35 am UTC

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Science

One mole of any gas at STP has a volume of 22.4 L. So first determine the number of moles of gas you have. 67.2/22.4 = 3 moles of H2 One mole of any substance contains Avogadro's number of atoms =...

Latest answer posted November 1, 2011 9:13 pm UTC

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Science

Nanochemicals are chemicals generated by using nanomaterials, materials which have size on nanometer dimensions. The nanochemicals are used in a variety of applications, including chemical warfare,...

Latest answer posted April 17, 2015 9:34 am UTC

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Science

Physical changes are those changes where the chemical composition remains the same, even though the appearance or phase may change. Conversion of water to ice or vapors is a physical change, since...

Latest answer posted March 3, 2016 1:15 pm UTC

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Science

HCl can exists in two forms. It is either in aqueous or in gaseous form. It can be formed from Hydrogen and chlorine ions or gasses. Hydrogen Chloride aqueous delta H f = -92.30 Hydrogen Chloride...

Latest answer posted November 6, 2012 6:17 am UTC

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Science

The chemical equations for which the enthalpy change is given are: CH4(g) `->` C(s) + 2H2 (g) `Delta H` = +74.85 kJ/mol ...(1) CH4(g) + 2O2 (g) `->` CO2(g) + 2H2O (g) `Delta H` = -802.3...

Latest answer posted August 1, 2012 6:39 pm UTC

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