Answer:
Protons= 11
neutrons= 12
electrons = 10
Explanantion:
Look for Na on periodic table
Atomic Number = 11
Atomic Mass = 23 (round it to be an integer)
Number of protons = Atomic number = 11
Number of neutrons = Atomic mass - atomic number = 23-11 =12
Number of electrons = 11 - e = ´+1 , electrons = 10
A b c d c would be your answer
Answer:
2.7 g/cm³
Explanation:
Step 1: Calculate the mass of kerosene
The mass of the full beaker (mFB) is equal to the sum of the masses of the empty beaker (mEB) and the mass of the kerosene (mK).
mFB = mEB + mK
mK = mFB - mEB
mK = 60 g - 20 g = 40 g
Step 2: Calculate the density of kerosene
Density (ρ) is an intrinsic property of matter. It can be calculated as the quotient between the mass of kerosene and its volume.
ρ = m/V
ρ = 40 g/15 cm³ = 2.7 g/cm³
So they can prove there hypothesis is correct or have an understanding.