Answer:
d) cut the large sized Cu solid into smaller sized pieces
Explanation:
The aim of the question is to select the right condition for that would increases the rate of the reaction.
a) use a large sized piece of the solid Cu
This option is wrong. Reducing the surface area decreases the reaction rate.
b) lower the initial temperature below 25 °C for the liquid reactant, HNO3
Hugher temperatures leads to faster reactions hence this option is wrong.
c) use a 0.5 M HNO3 instead of 2.0 M HNO3
Higher concentration leads to increased rate of reaction. Hence this option is wrong.
d) cut the large sized Cu solid into smaller sized pieces
This leads to an increased surface area of the reactants, which leads to an increased rate of the reaction. This is the correct option.
1.34 moles are in 135g of Teflon.
Explanation:
Molecular formula of teflon is (C2H4)n
mass of teflon = 135 grams
atomic mass of teflon = 100.01 gram/mole
number of moles of teflon = ?
Formula used to calculate number of moles in a substance is given as:
number of moles = 
putting the values in the above equation:
number of moles = 
number of moles = 1.34 moles
Teflon is polymer which is used for making non-stick coating, in 135 grams of teflon there are 1.34 moles in it.
The monochloroderivatives will be obtained by substituting chemically non equivalent hydrogen with chlorine atom, one by one
So the possible monochloro derivatives of 2,4-dimethylpentane (figure 1) are shown in figure (2)
Answer:
B only
Explanation:
Using the VSEPR principle, the electron bond pairs and the lone pairs on the middle atom help us predict the structure of the molecule. The shape of a molecule is determined by the position of the nucleus and its electrons. The electrons and the nucleus settle in positions that minimize repulsion and maximize attraction.
From Earth's<span> density we can estimate what elements must compose the </span>Earth; an iron core<span> just happens to estimate </span>Earth's<span> mass the best. Now from energy waves, geologists use seismometers to measure movements in </span>Earth's<span> interior (e.g. Earthquakes), These energy-waves form compressional and shear waves</span>
