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Hey There!</h2><h2>
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Answer:</h2>
<h2>____________________________________</h2><h2><u>PERIODIC TABLE</u>:</h2>
The periodic table, arranges the chemical elements ascording to their recurring properties. The number of each element corresponds to the number of protons in its nucleus.
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Groups and Periods</h3>
There are 8 groups and 7 periods in the periodic table.
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Each element within a group has similar physical or chemical properties because of its atom's outermost electron shell. The outermost shell of every element in a specific group has same number of valence shell (most chemical properties are determined by the the outermost valence shell electron). The group number of an element represents the number of electrons in its outermost orbit. This shows that elements arranged in the same group have the same number of electrons in their outermost orbit.
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Sodium and Potassium</h3>
Sodium and Potassium belong to the same group i.e. GROUP 1 which is also called S BLOCK Group or IONIC GROUP. They have the similar properties,
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Properties of S block Elements
1- They are soft metals
2- possess low melting and boiling points
3- They have the largest atomic radii in their corresponding periods
4- are good conductors of heat and electricity.
5- They have low values of ionization energies and are hence highly electropositive.
<h2>_____________________________________</h2><h2>Best Regards,</h2><h2>'Borz'</h2><h2 />
A) spines
A herbivore, or a plant eating animal, will be much less likely to go after a plant that is covered in spines. Spines make the plant painful and difficult to eat.
Answer:
81.71%
Explanation:
One mole of propane contains 3 moles of carbon atoms and 8 moles of hydrogen atoms, as seen from the molecular formula of 
. In order to calculate the percent of carbon in propane by mass, we need to remember that %w/w (or percent mass) formula states that:
That is, we need to divide the mass of the component of interest by the total mass of the compound and multiply by 100 to obtain the percentage.
For simplicity, let's take 1 mole of propane and find the mass of 1 mole (hence, we'll be finding the molar mass of propane). To do that, we add the 3 molar masses of carbon and 8 molar masses of hydrogen to obtain a total of:
Now that we have the molar mass of propane, we also need to find the total mass of carbon in 1 mole of propane. We know that we have a total of 3 moles of carbon which corresponds to:
Dividing the mass of carbon present by the total mass of the compound will yield the mass percentage as defined by the formula we introduced:
In your hand, the ball has higher potential energy than kinetic because it is still off of the ground but it isn't moving so there is no kinetic. As the ball rises, its potential and kinetic energy increases. At its peak, it has very high potential energy and very low kinetic energy. As it falls, the potential energy decreases but kinetic does not.
Ans: 15.1 grams
Given reaction:
Na2CO3 + Ca(OH)2 → 2NaOH + CaCO3
Mass of Na2CO3 = 20.0 g
Molar mass of Na2CO3 = 105.985 g/mol
# moles of Na2CO3 = 20/105.985 = 0.1887 moles
Based on the reaction stoichiometry: 1 mole of Na2CO3 produces 2 moles of NaOH
# moles of NaOH produced = 0.1887*2 = 0.3774 moles
Molar mass of NaOH = 22.989 + 15.999 + 1.008 = 39.996 g/mol
Mass of NaOH produced = 0.3774*39.996 = 15.09 grams
