D = 0.2 g / ml = 0.2 g / cm³
For example, density of steel is 7.85 g / cm³.
Density of pure water is 1.0 g/cm³. An object which has a density < 1.0 g/cm³ will float in water.
Answer: Material that has a density of 0.2 g/ml ( 0.2 g/cm³ ) is good for making couch cushions.
Answer:
Number of proton is 11
Number of neutrons is 12
Number of electrons is 10
Explanation:
For a neutral Na, Sodium atom:
The mass number P+N = 23
Atomic number(E or P) = 11
A charged Na atom that has lost an electron is positively charged and so:
Number of proton = 11 (Still the same)
Number of neutrons = 12
Number of electrons = 11-1=10 (the atom has lost an electron)
If an atom loses electron, it becomes positively charged ie P>E
0.72 mole of oxygen would produce 320.4 kJ of heat.
<u>Explanation:</u>
CH₄ (g) + 2O₂ (g) → CO₂ (g) + 2H₂O (ℓ) + 890kJ
According to the equation,
2 moles of O₂ produces 890 kJ of heat
So, 0.72 moles of O₂ will produce:
Therefore, 0.72 mole of oxygen would produce 320.4 kJ of heat.
Answer:
E = 12.92 × 10^(-16) J
Explanation:
Formula for energy is;
E = hc/λ
Where;
h is Planck's constant = 6.63 x 10^(-34) J.s
c is speed of light = 3 × 10^(8) m/s
λ is wavelength = 0.154 nm = 0.154 × 10^(-9) m
E = (6.63 x 10^(-34) × 3 × 10^(8))/(0.154 × 10^(-9))
E = 12.92 × 10^(-16) J
