It is advisable to wear long sleeve when when a student is working in a chemistry lab so that to protect arms from lab chemicals. when someone enter the chemistry lab to wort or to study should be well prepared with appropriate gears and security measure to avoid injury.
Answer:
more rapid
Explanation:
A higher temperature of fresh concrete results in a more rapid hydration of cement. This causes reduction in the setting time of the cement, also known as accelerated setting of the cement.
It also reduces the workability of the concrete; as it makes the movement of aggregates harder by reducing the lubricating effect of the cement.
Mass = mass/molar mass of ch3ch2nh2
the molar mass of CH3CH2NH2 = 12 +(1x3)+12+(1 x2)+14+(1x2) =45 g/mol
moles is therefore = 1.50g /45g/mol = 0.033 moles
I believe the correct answer true. According to the law of conservation of mass, in a chemical reaction the total starting mass of all the reactants equals the total final mass of all the products. This law states that mass cannot be created or be destroyed. So, the total mass that goes in a process should be equal to the mass that goes out the process. This is true for chemical reactions and physical processes. It is Antoine Lavoisier who described this and is a basic principle used in physics and in chemistry. Mass, unlike energy, cannot be transformed to any form so however the transformation happens the mass should be constant.
Answer:
Molar concentration of the weak acid solution is 0.0932
Explanation:
Using the formula: 
Where Ca = molarity of acid
Cb = molarity of base = 0.0981 M
Va = volume of acid = 25.0 mL
Vb = volume of base = 23.74 mL
na = mole of acid
nb = mole of base
Since the acid is monopromatic, 1 mole of the acid will require 1 mole of NaOH. Hence, na = nb = 1
Therefore, 
Ca = 0.0981 x 23.74/25.0
= 0.093155 M
To 4 significant figure = 0.0932 M
