Silver is A precious shiny grayish-white metal, the chemical element of atomic number 47. Silver is sometimes found in nature in metallic form. It forms a sulfide mineral Ag 2 S called acanthite. Mineral forms of silver include sulfides formed with antimony called Stephanite, miargyrite and pyrargyrite. Silver is a naturally occurring element on the periodic table and can be found in natural deposits throughout the world. As such, it was discovered in 5000 BC, but not invented, by people.
Through hypothesis and experiments
Fossil fuels are buried geologic deposits of organic materials. They are made of decaying plants and animals that have been turned into to natural oil. A few examples of fossil fuels are coal and oil.
Answer:
Temperature of the water
Explanation:
In every study, there must be independent and dependent variables. An independent variable is the variable that is changed in order to obtain a response. In this case, the temperature of the water is being changed, the response in this experiment is the respiration rate of the goldfish.
Thus the respiration rate of the goldfish is the dependent variable because it is controlled by the temperature of the water and changes accordingly.
Summarily, the independent variable is the temperature of the water while the dependent variable is the respiration rate of the goldfish.
Answer:
= 67.79 g
Explanation:
The equation for the reaction is;
4Cr(s)+3O2(g)→2Cr2O3(s)
The mass of O2 is 21.4 g, therefore, we find the number of moles of O2;
moles O2 = 21.4 g / 32 g/mol
=0.669 moles
Using mole ratio, we get the moles of Cr2O3;
moles Cr2O3 = 0.669 x 2/3
=0.446 moles
but molar mass of Cr2O3 is 151.99 g/mol
Hence,
The mass Cr2O3 = 0.446 mol x 151.99 g/mol
<u> = 67.79 g
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