Scientific Notation - PLEASE HELP!

Before it was launched, a helium-filled balloon had a pressure of 101 kPa at a temperature of 20°C. At an altitude of 15 000 m,

bogdanovich [222]

Answer:

5.54 m³.

Explanation:

We should use the ideal gas law: <em>PV = nRT,</em>

where, P is the pressure of the gas in atm,

V is the volume of the gas in L,

n is the number of moles in mole,

R is the general gas constant (R = 0.082 L.atm/mol),

T is the temperature of the gas in K.

<em>We have two different cases at different (P, V and T) while the number of moles of He and R is constants.</em>

<em>∴ (P₁V₁) / (T₁) = (P₂V₂) / (T₂).</em>

We can use P in KPa and V in m³ that the conversion factor can be canceled by division, but we should use T in K because its conversion factor is additive value.

P₁ = 101.0 kPa, V₁ = <em>??? m³</em>, and T₁ = (20 °C + 273) = 293.0 K.

P₂ = 11.7 kPa, V₂ = 35.4 m³, and T₂ = (-56 °C + 273) = 217 K.

∴ The initial volume (V₁) = (P₂V₂T₁) / (P₁T₂) = (11.7 kPa)(35.4 m³)(293.0 K) / (101.0 kPa)(217.0 K) = (121354.74) / (21917) = 5.537 m³ ≅ 5.54 m³.

7 0

3 years ago

Given the speed of light (3.00 × 108 m/s) and a wavelength 5.9 × 10-7 m, what is the frequency?

Cerrena [4.2K]

Wavelength x Frequency = Speed

So, 5.9 x 10^-7 x F = 3 x 10^8

Rearranging the equation, we get:
F = (3 x 10^8)/(5.9 x 10^-7) = 5.08 x 10^14 Hz

Hope I helped!! xx

5 0

3 years ago

If the partial pressure of oxygen outside of a cell is 100 mmHg and the partial pressure of oxygen inside of a cell is 25 mmHg,

mrs_skeptik [129]

" There will be a net movement of oxygen from outside the cell to inside the cell " Statement is True.

Explanation:

The partial pressure for oxygen in alveoli is greater under normal circumstances, and oxygen moves neatly into the blood. In addition, the partial carbon dioxide pressure throughout the blood usually is higher, such that carbon dioxide migrate clearly into the alveoli.

The few common molecules which can traverse the cell membrane by absorption (or diffusion of a sort recognized as osmosis) are water, carbon dioxide and oxygen. Metabolism is typically oxygen-needed, which is lowest in the cell within the animal and plant, so that net oxygen flows to the cell.

3 0

4 years ago

Calculate the pressure exerted on the floor when an elephant who weighs 2400 N

Inessa05 [86]

Answer:

The answer is

Explanation:

The pressure exerted by an object given the force of the object and the area can be found by using the formula

$P = \frac{f}{a} \\$

where

P is the pressure

f is the force

a is the area

From the question

f = 2400 N

a = 0.4 m²

So we have

$P = \frac{2400}{0.4} \\$

We have the final answer as

Hope this helps you

8 0

3 years ago

Use tabulated standard electrode potentials to calculate the standard cell potential for the following reaction occurring in an

SVETLANKA909090 [29]

Answer : The standard cell potential of the reaction is, -1.46 V

Explanation :

The given balanced cell reaction is,

$3Pb^{2+}(aq)+2Cr(s)\rightarrow 2Cr^{3+}(aq)+3Pb(s)$

Here, chromium (Cr) undergoes oxidation by loss of electrons and act as an anode. Lead (Pb) undergoes reduction by gain of electrons and thus act as cathode.

The standard values of cell potentials are:

Standard reduction potential of lead $E^0_{[Pb^{2+}/Pb]}=-0.13V$