All categories

3 years ago

Why does helium have more spectral lines than hydrogen?

1 answer:

8 0

This is because Helium has two valence electrons compared to Hydrogen which has only one. Helium has more energy levels for an electron to jump thus more spectral lines to occur. The spectral lines relating to each change of energy level would be more grouped together and hence the greater chance of them falling in the visible range.

You might be interested in

A small cork is charged to +4.50 mC. Find the number of excess elementary charges (protons or electrons)

Irina-Kira [14]

Answer:

The third choice: $2.81*10^{16} \: \text{protons}$

Explanation:

The cork is positively charged, therefore we know tat there must be excess of positively charged protons present.

The charge $p^+$ of a proton is

$p^+ = +1.6*10^{-19}C$ ;

therefore, the number $n$ that makes up a charge of $+4.5mC$ is

$n = \dfrac{+4.5mC}{+1.6*10^{-19}C} = \dfrac{+4.5*10^{-3}C}{+1.6*10^{-19}C}$

$\boxed{n =2.81*10^{16} \: \text{protons}}$

which is the 3rd choice.

7 0

3 years ago

holiday lights are often connected in series and use special lamps that short out when the potential difference across a lamp in

Nuetrik [128]

Explanation:

If there isn't the shorting mechanism, the whole set will be blown if anyhow one lamp burns out. Since having blown out several lamps and then shorted, the overall resistance of the remaining operating lamps will be decreased resulting in an increased working current that is adequate to blast the fuse.

4 0

4 years ago

Water that contains a larger than normal amount of __________ is still safe to drink.

Lynna [10]

Answer:

Water that contains a larger than normal amount of magnesium is still safe to drink.

Explanation:

Sulfur, lead and arsenic are harmful metals that are toxic to human health. Although magnesium present at high concentrations (above approximately 250 mg/l each) can have a laxative effect. However, data suggest that consumers adapt to these levels as exposures continue.

4 0

3 years ago

Read 2 more answers

Suppose 9.30 3 105 J of energy are transferred to 2.00 kg of ice at 0°C. (a) Calculate the energy required to melt all the ice i

Ratling [72]

Answer:

(a) 672000 J

(b) 258300 J

(c) 30.75 °C

Explanation:

(a) Energy required to melt the ice = Latent heat of fusion of ice

Latent heat of fusion of ice (Q₁) = lm............................. Equation 1

Where l = specific latent heat of fusion of ice, m = mass of ice

Given: m = 2.00 kg

Constant : l = 336000 J/kg

Substituting these values into equation 1,

Q₁ = 336000 × 2

Q₁ = 672000 J.

Energy required to melt the ice = 672000 J

(b) The Energy remains to raise the temperature of the liquid water = Total Energy - Energy requires to melt the ice.

Given: Total Energy = 9.303 × 10⁵ J, = 930300 J

Energy remain to raise the temperature of the liquid water =

930300 - 672000

Total Energy = 258300 J

Energy remain to raise the temperature of the liquid water = 258300 J.

(c): Q = cmΔT ............. equation 2

Where c = specific heat capacity of water, m = mass of water, ΔT = change in temperature, Q = Energy required to change the temperature of liquid water

Making ΔT the subject of formula in the equation above,

ΔT = Q/cm........................................... Equation 3

Given: m = 2.00 kg, Q = 258300 J

Constant: C = 4200 J/kg. K

Substituting these values into equation 3

ΔT = 258300/(4200×2)

ΔT = 258300/8400

ΔT = 30.75 K

But ΔT = T₂ - T₁

Where T₁ initial temperature, T₂ = final Temperature

T₂ = T₁ + ΔT,

Given: T₁ = 0 °C

Therefore,

T₂ = 30.75 + 0 = 30.75

T₂ = 30.75 °C

Final temperature of water = 30.75 °C

6 0

3 years ago

Restaurant owners agree to comply with state, but not federal, health

Charra [1.4K]

Answer:

False.

Explanation:

A public health license can be defined as series of privileges and authority granted to a practitioner in the public domain, to offer services to the general public after admitting to comply with the standards, rules and regulations set aside by health regulatory agencies and the government (both state and federal).

This ultimately implies that, all restaurant owners must have met the minimum requirements (criteria) and agree to comply with all the standards, rules and regulations with respect to public health before they are endorsed and then given a license to practice or operate by the appropriate agency or authorities.

Hence, restaurant owners agree to comply with state, federal, and health regulations when applying for a public health license.

4 0

3 years ago