Gold is also highly malleable and ductile which means it is able to be hammered into many shapes and can be drawn into long thin wires. The colour of this metal, a butter yellow with a metallic lustre, attracts many and is one of its most common recognised characteristics. Gold also has great infared reflectivity and has very low reactivity while in the presence of other elements. Gold’s resistance to corrosion is also what makes this metal so durable. 2.
The atomic radius is 197 and atomic volume is 29.9 cc/mol. Covalent radius is 174 and the ionic radius is 99. The oxidation states is 2. Calcium has been known since the first century, when the ancient Romans were known to make lime from calcium oxide. The word Calcium comes from the word "calcis" in Latin which means "lime".
Synthesis of Colloidal Gold. This is one of the most effective methods of producing gold nanoparticles which was founded by Eah group. In this method we reduce HAuCl4 and NaBH4 to generate gold nanoparticles in water. The easiness of this method is that the final gold particles can be easily tunneled from 3.2 to 5.2 nm. We will look at the synthesis of colloidal gold in water and then coating our particle with DDT by this method on a small scale.
Properties of metal nanoparticles are different from those of bulk materials made from the same atoms. For example, silver metal is grayish, but colloidal silver from this synthesis is a clear yellow. The striking effect of nanoparticles on color has been known since antiquity when tiny metal particles were used to color glass in church wndows. Silver particles stained the glass yellow, while gold particles were used to produce ruby glass. Synthesis of Colloidal Ag Colloidal silver is made by adding an excess of the reducing agent sodium borohydride, NaBH4 to silver nitrate, AgNO3 .
Materials: fluorescent screen gold foil radiation source (positively charger alpha particles) Procedure: Rutherford set up an alpha source. The alpha part ices ere helium nuclei, two protons and two neutrons. A lead block with a slip served as the source. A radioactive substance giving alpha particle emission was put inside. The slit acted as the only means of escape for the particles.
Tessa Lollar Elemet report: Tin Chemistry- Mrs.Denton 09/26-03/11 What exactly is Tin? Tin is a chemical element that belongs to the main metal group. Its symbol is Sn, because its Latin name is Strannum. Anglo-Saxon origin being tin, came from being Named after Etruscan god, Tinia. There is evidence that Stone Age men used it 3,500 years ago.
Class data: (in grams) *.81 *.75 2.3 *1.72 *1.39 2.37 2.06 *1.03 2.02 2.18 2.3+2.06+2.02+2.37+2.18=10.93 10.93/5= 2.186 Class average mass of zinc in a penny is 2.19g 3. How much (in g) of the penny was made of copper? Mass of penny 2.47g Mass of zinc - .81g =
Archimedes’ method Object Mass (g) Mass of Displaced Water (g) Volume of Displaced Water (mL) Density (g/mL) Metal Bolt 42.5 25 25 25 Magnet 16.2 3.5 3.5 3.5 Questions: An unknown, rectangular substance measures 3.6 cm high, 4.21 cm long, and 1.17 cm wide. If the mass is 21.3 g, what is this substance’s density (in grams per milliliter)? 1.2 g/ml A sample of gold (Au) has a mass of 26.15 g. Given that the theoretical density is 19.30 g/mL, what is the volume of the gold sample? 1.35 mL What would happen if you dropped the object into the beaker while using the Archimedes’ Principle method instead of submerging the object? The measurements would be the same.
Station 7 deals with volatility and if the substances are able to evaporate at normal temperatures. Sand was non-volatile its great composition and able to withstand anything because of its strong particles. From the results of sand, it is determined network covalent because it has high melting point and boiling points and is insoluble in water. The secondary substance is salt and its formula is written as NaCl. Salt is an ionic bond, which is a type of chemical bond that
37 Rb Rubidium 85.4678 Atomic Number: 37 Atomic Weight: 85.4678 Melting Point: 312.46 K (39.31°C or 102.76°F) Boiling Point: 961 K (688°C or 1270°F) Density: 1.53 grams per cubic centimeter Phase at Room Temperature: Solid Element Classification: Metal Period Number: 5 Group Number: 1 Group Name: Alkali Metal What's in a name? From the Latin word for deepest red, rubidus. Say what? Rubidium is pronounced as roo-BID-i-em. History and Uses: Rubidium was discovered by the German chemists Robert Bunsen and Gustav Kirchoff in 1861 while analyzing samples of the mineral lepidolite (KLi2Al(Al, Si)3O10(F, OH)2) with a device called a spectroscope.