Explanation:
B. The light bends in the water causing the straw to look different.
This happens due to the refraction of light.
Answer:
pH change is -0.07
Explanation:
Using H-H equation for acetic acid:
pH = pKa + log [Acetate salt] / [Acetic acid]
Replacing:
pH = 4.74 + log[1.188M] / [1.188M]
pH = 4.74
The HCl reacts with sodium acetate producing acetic acid, thus:
HCl + CH₃COONa → CH₃COOH + NaCl
That means the final moles of sodium acetate are initial moles - moles of HCl and moles of acetic acid are initial moles + moles of HCl.
As the volume of the buffer is 1.0L, initial moles of both substances are 1.188moles. After reaction, the moles are:
sodium acetate: 1.188mol - 0.1mol = 1.088mol
Acetic acid: 1.188mol + 0.1mol = 1.288mol
Using again H-H equation:
pH = 4.74 + log[1.088M] / [1.288M]
pH = 4.67
pH change is: 4.67 - 4.74 = -0.07
Chemical reactions can be broadly classified into two categories from the context of heat requirement. These include; endothermic and exothermic reactions.
Endothermic reactions proceed with the absorption of heat while exothermic reactions are accompanied by the evolution of heat.
1) Oxidation of iron involves reaction of elemental iron with oxygen to form iron oxide (rust). This is essentially a corrosion reaction in which the metallic bonds in Fe are broken and new bonds between Fe and O are formed, This is an exothermic reaction
4Fe + 3O2 → 2Fe2O3
Ans D)
2) The process of condensation i.e. phase change liquid to solid (or gas to liquid) involves release of heat to the surroundings, hence it will be an exothermic reaction.
Ans B)
3) Specific heat is the amount of heat required to raise the temperature of 1 g of a substance by a 1 C. Typically, liquids and gases are used as coolants. For a coolant to be efficient, it must have a high specific heat.
Ans B)
Answer:a law stating that the volume of an ideal gas at constant pressure is directly proportional to the absolute temperature
Explanation:
Hydrogen- and Oxygen Atoms combine to form a whole net molecule called H20 (Water), which has completely different properties and pure water can't ignite
