Answer: I think its C or B
Explanation: Hope this was helpful....
Answer:
Weigh 4.5 grams of sodium hydroxide and add it to the dry volumetric flask of 450 mL followed by small amount of water to dissolve all the NaOH .After this add the water upto tye mark of 450 mL.
Explanation:
Molarity of the solution is the moles of compound in 1 Liter solutions.
Mass of NaOH = x
Molar mass of NaOH = 40 g/mol
Volume of the NaOH solution = 450 mL =- 0.450 L ( 1 ml = 0.450 L)
Molarity of the solution of NaOH = 0.250 M
Solving for x:
x = 4.5 g
Weigh 4.5 grams of sodium hydroxide and add it to the dry volumetric flask of 450 mL followed by small amount of water to dissolve all the NaOH .After this add the water upto tye mark of 450 mL.
Answer:
Atomic number of this isotope = 77
Explanation:
Given that,
Mass number = 193
No of neutrons = 116
We need to find the atomic no of this isotope.
We know that,
Atomic mass = No of protons + No. of neutrons
Also, atomic no = no of protons
So,
Atomic mass = atomic no + No. of neutrons
⇒ Atomic no = Atomic mass - no of neutrons
Atomic no = 193 - 116
Atomic no = 77
Hence, 77 is the atomic no of the isotope.
The mass of lime that can be produced from 4.510 Kg of limestone is calculated as below
calculate the moles of CaCO3 used
that is moles =mass/molar mass
convert Kg to g = 4.510 x1000 =4510g
= 4510 / 100 =45.10 moles
CaCO3 = CaO +O2
by use of mole ratio between CaCO3 to CaO (1:1) the moles of CaO is also= 45.10 moles
mass of CaO = moles x molar mass
45.10 x56 = 2525.6 g of CaO
Oxygen is a chemical element with symbol O and atomic number 8. Classified as a nonmetal, Oxygen is a gas at room temperature.
