The balanced equation for the reaction between KOH and HBr is as follows;
KOH + HBr --> KBr + H₂O
stoichiometry of KOH to HBr is 1:1
number of KOH moles reacted - 0.25 mol/L x 0.015 L = 0.00375 mol
according to molar ration
number of KOH moles reacted = number of HBr moles reacted
number of HBr moles reacted - 0.00375 mol
if 12 mL of HBr contains - 0.00375 mol
then 1000 mL of HBr contains - 0.00375 mol / 12 mL x 1000 mL = 0.313 mol
therefore molarity of HBr is 0.313 M
Answer:
Hypsochromic shift.
The second solvent is more polar.
Explanation:
Compound A + Solvent 1 = red
Compound A + Solvent 2 = orange
Since orange has a smaller wavelength than red, the electronic transition observed when the compound A is dissolved in solvent 2 has a higher energy.
A band transition to a lower wavelength and higher energy is called a hypsochromic shift.
The change in the color due to the solvent is called solvatochromism. Usually, when the hypsochromic shift is observed (negative solvatochromism) it means that the solvent is more polar.
Answer : The answer is, 
Explanation :
Scientific notation : It is defined as the way or representation of expressing the number that are too big or too small that is written in the decimal form. That means always written in the power of 10 form.
For example : 8000 is written as, 
in this notation, the significant figure is, 1 but 
in this notation, the significant figures are, 2
The given problem are :
According to the divide and multiplication rules of scientific figures, the final answer is only as precise as the value with the least number of significant figures.
Hence, the answer is,
Answer:
0.4444 g/cm³ ≅ 0.44 g/cm³ (2 significant figures).
Explanation:
<em>d = m/V,</em>
where, d is the density of the material (g/cm³).
m is the mass of the material (m = 28 g).
V is the volume of the material (V = 63.0 cm³).
<em>∴ d = m/V </em>= (28 g)/(63.0 cm³) = <em>0.4444 g/cm³ ≅ 0.44 g/cm³ (2 significant figures).</em>
