J.J Thompson’s model shows a sphere with electrons that are moving around freely. However, Thompson’s model does not show protons or neutrons. The model that we have today gives a clearer structure showing protons, neutrons, and electrons inside an atom.

6 0

3 years ago

Find the density of a substance whose volume is 10.0 mL and whose mass is 5.000 g

scoray [572]

Answer:

.5 gm / ml

Explanation:

Density is defined as mass/ volume

so density of this substance is 5 gm / 10 ml = .5 gm/ ml

5 0

2 years ago

Part A Transmutation is the process of transforming one element into another through nuclear reactions. What will be the nuclide

S_A_V [24]

Answer: The isotope produced after the transmutation process of Cf-249 and C-12 is $_{104}^{257}\textrm{Rf}$

Explanation:

Transmutation is defined as the process where one chemical isotope gets converted to another chemical isotope. The number of protons or neutrons in the isotope gets changed.

The chemical equation for the reaction of Californium-249 nucleus with Carbon-12 nucleus follows:

$_{98}^{249}\textrm{Cf}+_6^{12}\textrm{C}\rightarrow _{Z}^{A}\textrm{X}+4_0^1\textrm{n}$

In a nuclear reaction, the total mass and total atomic number remains the same.

To calculate A:

Total mass on reactant side = total mass on product side

249 + 12 = A + 4

A = 257

To calculate Z:

Total atomic number on reactant side = total atomic number on product side

98 + 6 = Z + 0

Z = 104

Hence, the isotope produced after the transmutation process of Cf-249 and C-12 is $_{104}^{257}\textrm{Rf}$

5 0

3 years ago

The retina of a human eye can detect light when radiant energy incident on it is at least 4.00 × 10−17 J. For light of 535−nm wa

VLD [36.1K]

Answer:

1080 photons

Explanation:

ΔE = hc/λ => Energy per photon

h = 6.63 x 10⁻³⁴ j·s

c = 3 x 10⁸ m/s

λ= 535 nm = 5.35 x 10⁻⁷ m

ΔE/photon = (6.63 x 10⁻³⁴ j·s)(c = 3 x 10⁸ m/s)/(5.35 x 10⁻⁷ m) = 3.71 x 10⁻¹⁹ j/photon

For #photons in 4.00 x 10⁻⁷ j = (4.00 x 10⁻⁷ j) / (3.71 x 10⁻¹⁹ j/photon) = 1076 photons ≅ 1080 photons (3 sig. figs.)

7 0

4 years ago