b.bromine
c.carbon
d.oxygen
The correct option is A.
The elements in the periodic table are arranged into groups and columns on the basis of their atomic number. Elements with similar number of electrons in their outermost shells fall in the same group of the periodic table. There are some properties of the elements that changes both in the periods and the groups of the periodic table and one of these is conductivity. Conductivity increases across period 3 from sodium to aluminium and then decrease to silicon. Thus, sodium is a good conductor of electricity.
In 6.3 moles of calcium, there are approximately 3.79 x 10²⁴ atoms. This is calculated using Avogadro's number (6.022 x 10²³), which provides the number of atoms in a mole.
To find the number of atoms in 6.3 moles of calcium, you need to use Avogadro's number, which is 6.022 x 10²³. This number, known as Avogadro's constant, is the number of atoms or molecules in one mole of any substance. Therefore, you would calculate the number of atoms as follows:
6.3 moles of calcium × (6.022 x 10²³ atoms/mole) = 3.79 x 10²⁴ calcium atoms.
So, 6.3 moles of calcium have approximately 3.79 x 10²⁴ calcium atoms.
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Henri Becquerel was studying properties of x-rays
B.They can only be formed by decay of swamp plants.
C.They take millions of years to form.
D.They can only be formed deep under the sea.
The answer is: C. They take millions of years to form.
Fossil fuel is a fuel formed by anaerobic decomposition of buried dead organisms.
If there was oxygen the organic matter would not decomposed and formed oil and gas, because there would be reaction of oxidation.
The age of the organisms and their resulting fossil fuels is typically millions of years
Fossil fuel is mixture (solution) consist of several different hydrocarbons (alkanes, alkenes...), aromatic compounds.
Answer:
An SN2 (substitution nucleophilic bimolecular) reaction
Explanation:
This is a type of organic reaction that involves a nucleophile attacking an electrophilic center, resulting in the displacement of a leaving group from that center. This type of reaction typically occurs at a saturated carbon atom, where the nucleophile displaces a leaving group attached to that carbon atom. The reaction is bimolecular because it involves the collision of two molecules, the nucleophile and the substrate.