The pH of pure water is neutral because the concentration of hydronium ions equals that of hydroxide ions.
Answer: Option A
<u>Explanation:</u>
Water is one of the most important constituents of living being. It is said that there is no life without water. So that water need to neutral in nature to save life. Pure water is composed of hydronium 
and hydroxide 
ions. It is known that hydronium ions are acidic in nature with concentration of 
.
Similarly, the hydroxide ions which are basic in nature will be in same concentration as that of hydronium ions. So, as the concentration of basic and acidic elements are equal with the same strength of pH, the combination of these ions lead to formation of pure water with the pH being neutral.
Answer: A substance that produces hydroxide ions when placed in water is base.
Explanation:
Bases are the substance:
- Which gives negatively charged hydroxide(
) ions in aqueous solution.
- Which have pH value ranging from 7 to 14.
Where as acid gives positively charged hydronium ion(
) in aqueous solution.
Answer:
They dissociate into positive and negative ions in the solution.
Explanation:
NaCl when dissolved in water dissociates into Na+ ion and Cl- ion.
The density of a material is the mass of the material per unit volume. Here the weight of the same metal is 44.40g, 40.58g and 38.35g having volume 4.8 mL, 4.7 mL and 4.2 mL respectively. Thus the density of the metal as per the given data are, 
= 9.25g/mL, 
= 8.634g/mL and 
= 9.130g/mL respectively.
The equation of the standard deviation is √{∑(x - 
)÷N}
Now the mean of the density is {(9.25 + 8.634 + 9.130)/3} = 9.004 g/mL.
The difference of the density of the 1st metal sample (9.25-9.004) = 0.246 g/mL. Squaring the value = 0.060.
The difference of the density of the 2nd metal sample (9.004-8.634) =0.37 g/mL. Squaring the value = 0.136.
The difference of the density of the 3rd metal sample (9.130-9.004) = 0.126 g/mL. Squaring the value 0.015.
The total value of the squared digits = (0.060 + 0.136 + 0.015) = 0.211. By dividing the digit by 3 we get, 0.070. The standard deviation will be 
. Thus the standard deviation of the density value is 0.265g/mL.
Answer:
25.11 g.
Explanation:
- It is clear from the balanced equation:
<em>Ag₂O + 2HCl → 2AgCl + H₂O.</em>
<em></em>
that 1.0 mole of Ag₂O reacts with 2.0 moles of HCl to produce 2.0 mole of AgCl and 1.0 moles of H₂O.
- 7.8 g of HCl reacts with excess Ag₂O. To calculate the no. of grams of Ag₂O that reacted, we should calculate the no. of moles of HCl:
<em>no. of moles of HCl = mass/atomic mass</em> = (7.9 g)/(36.46 g/mol) = <em>0.2167 mol.</em>
- From the balanced equation; every 1.0 mol of Ag₂O reacts with 2 moles of HCl.
∴ 0.2167 mol of HCl will react with (0.2617 mol / 2 = 0.1083 mol) of Ag₂O.
<em>∴ The mass of reacted Ag₂O = no. of moles x molar mas</em>s = (0.1083 mol)(231.735 g/mol) = <em>25.11 g.</em>
