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2 years ago

Atomic radii DECREASES as you move across a period. Why?

Chemistry

1 answer:

Lelechka [254]2 years ago

8 0

Explanation:

As you move across a period, you gain more electrons and become more electronegative. The electrons become very attracted to the protons in the nucleus. This causes the electrons to become closer to the nucleus, decreasing atomic radii and increasing density.

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NEED HELPPP PLSSSSSSSSSS

Leto [7]

I would pick the first option in the third option

4 0

2 years ago

A gas occupies 2.0 m3 at 100.0k and exerts a pressure of 100.0kPa. What volume will the gas occupy if the temperature is increas

Svetradugi [14.3K]

According to ideal gas equation, we know for 1 mole of gas: PV=RT
where P = pressure, T = temperature, R = gas constant, V= volume
If '1' and '2' indicates initial and final experimental conditions, we have
$\frac{P1V1}{P2V2} = \frac{T1}{T2}$

Given that: V1 = 100.0 kPa, T1 = 100.0 K, V1 = 2.0 m3, T2 = 400 K, P2 = 200.0 kPa

∴ on rearranging above eq., we get V2 = $\frac{P1V1T2}{T1} = \frac{100 X 2 X 400}{200X100}$
∴ V2 = 4 m3

7 0

2 years ago

Which is the limiting reagent in the following reaction given that you start with 15.5 g of Na2S and 12.1 g CuSO4? Reaction: Na2

NemiM [27]

Answer:

CuSO4

Explanation:

Na2S + CuSO4 → Na2SO4 + CuS

The reaction is balanced (same number of elements in each side)

To determine limiting reagent you need to know the moles you have of each.

Molar mass Na2S = 23 * 2 + 32 = 78

Molar mass CuSO4 = 63.5 + 32 + 16 * 4 = 159.5

Na2S mole = 15.5 / 78 = 0.2

CuSO4 mole = 12.1/159.5 = 0.076

*Remember mole = mass / MM

With that information now you have to divide each moles by its respective stoichiometric coefficient

Na2S stoichiometric coefficient : 1

Na2S : 0.2 / 1 = 0.2

CuSO4 stoichiometric coefficient: 1

CuSO4: 0.076 / 1 = 0.076

The smaller number between them its the limiting reagent, CuSO4

8 0

3 years ago

What is the frequency of a light that has a wavelength of 3.0 x 10 -7m?

alexdok [17]

Answer:

frequency of light (f) = 1 x 10¹⁵s⁻¹

Explanation:

Given Data:

Wavelength of light λ = 3.0 x10⁻⁷m

Frequency of light: to be calculated

Formula Used to find frequency:

f = V/λ ........................... (1)

where

f is the frequency

V is the velocity

λ is wavelength

Velocity of light = 3 x 10⁸ ms⁻¹

put the values in equation (1)

f = 3 x 10⁸ ms⁻¹ / 3.0 x10⁻⁷m

f = 1 x 10¹⁵s⁻¹

So the frequency of light = 1 x 10¹⁵s⁻¹

7 0

2 years ago

1. A given mass of air has a volume of 6.00 L at 80.0°C. At constant pressure, the temperature is

earnstyle [38]

3 L will be the final volume for the gas as per Charle's law.

Answer:

Explanation:

The kinetic theory of gases has two significant law which forms the backdrop of motion of gases. They are Charle's law and Boyle's law. As per Charle's law, the volume of any gas molecule at constant pressure is directly proportional to the temperature of the molecule.

V∝ T

Since, here two volumes are given and at two different temperatures with constant pressure. Then as per Charle's law, the relation between the volumes of air at different temperature will be

$\frac{V_{1} }{T_{1} }= \frac{V_{2} }{T_{2} }$

So in this case, V1 = 6 L and T1 = 80° C. Similarly, T2 = 40° C. So we have to determine the V2.

$\frac{6}{80}=\frac{V_{2} }{40}$

$V_{2}=\frac{6*40}{80}=3 L$

So, 3 L will be the final volume for the gas as per Charle's law.

4 0

2 years ago