Answer is: <span>concentration of fluoride in the water in parts-per-million is 1 ppm.
</span>Parts-per-million (10⁻⁶) is<span> present at one-millionth of a </span>gram per gram of sample solution, f<span>or example mg/kg.
</span>m(fluoride) = 500 g · 1000 mg/g = 500000 mg.
m(water) = d(water) · V(water).
m(water) = 1 kg/L · 500000 L.
m(water) = 500000 kg.
arts-per-million = 500000 mg ÷ 500000 kg = 1 mg/kg = 1 ppm.
Answer:
Heat flux = 13.92 W/m2
Rate of heat transfer throug the 3m x 3m sheet = 125.28 W
The thermal resistance of the 3x3m sheet is 0.0958 K/W
Explanation:
The rate of heat transfer through a 3m x 3m sheet of insulation can be calculated as:

The heat flux can be defined as the amount of heat flow by unit of area.
Using the previous calculation, we can estimate the heat flux:

It can also be calculated as:

The thermal resistance can be expressed as

For the 3m x 3m sheet, the thermal resistance is

Answer:
for more details are in the pic
Isotopes of same element has different number of neutrons with different masses and having same number of protons and electrons.
Radioactive isotopes are those isotopes which are radioactive in nature. The unstable nucleus results in the radioactivity process and this process will go on until the stable isotope (element) forms.
Thus, the nucleus of unstable isotopes of an element will decay leading to emission of radiation.
Answer:
ΔE = 5.02 x 10⁻¹⁹ j
Explanation:
ΔE (photon) = h·f = (6.63 x 10⁻³⁴ j·s)(7.57 x 10¹⁴ s⁻¹) = 5.02 x 10⁻¹⁹ j
h = Planck's Constant = 6.63 x 10⁻³⁴ j·s
f = frequency (given) = 7.57 x 10¹⁴ s⁻¹