Ask question

Ask question

All categories

3 years ago

13

Explain how scientists know the oxygen level in the atmosphere has changed because of plants. Could our atmosphere still be chan

ging?

1 answer:

alukav5142 [94]3 years ago

4 0

Answer:

Kya hova be Tera question koi nahi btaye ga

You might be interested in

An ideal gas has a density of 1.10×10−6 g/cm3 at 1.00×10−3 atm and 80.0 ∘c. identify the gas.

True [87]

From ideal gas equation that is pv =nRt
n=number of moles which can be written as the ratio between the weight of a gas that is mass and its molecular mass n=m/Mm
pv=(m/Mm)RT
density is=mass per unit volume
P=m/v by arranging the equation we get
R =0.082atm/mol/k
Mm=pRT/P=[(1.10 x10^-6 x1000g/l) xo.082 atm/mol/k x(80+273] /(1.00 x10^-3) =31.84 to the nearest ten is 32
hence the gas is oxygen

7 0

3 years ago

Why is sodium more reactive than lithium

Elis [28]

Answer:

Sodium is more reactive than lithium because as we move down a group it is easy to lose electrons as the number of shells increases and nuclear charge decreases. As valence electrons take part in chemical reaction and its easier to lose electrons as we move down a group chemical reactivity increases. Therefore, sodium is more reactive than lithium.

Explanation:

I gotcha I searched it up

4 0

4 years ago

Read 2 more answers

KClKCl has a lattice energy of −701 kJ/mol.−701 kJ/mol. Consider a generic salt, ABAB , where A2+A2+ has the same radius as K+,K

elena-14-01-66 [18.8K]

Explanation:

It is given that lattice energy is -701 kJ/mol.

Whereas it is known that realtion between lattice energy and radius is as follows.

Lattice energy $\propto \frac{Z_{+}Z_{-}}{r}$

where, $Z_{+}$ = +2, and $Z_{-}$ = -2

Therefore, lattice energy of AB = $4 \times \text{lattice energy of KCl}$

= $4 \times -701 kJ/mol$

= -2804 kJ/mol

Thus, we can conclude that lattice energy of the salt ABAB is -2804 kJ/mol.

6 0

3 years ago

A sample of He gas (3.0 L) at 5.6 atm and 25°C was combined with 4.5 L of Ne gas at 3.6 atm and 25°C at constant temperature in

LenKa [72]

Answer:

$P=3.7atm$

Explanation:

Hello,

In this case, it is possible to determine the pressures of both helium and neon as shown below:

$n_{He}=\frac{P_{He}V_{He}}{RT}=\frac{5.6atm*3.0L}{0.082\frac{atm*L}{mol*K}*298.15K} =0.688molHe\\\\n_{Ne}=\frac{P_{Ne}V_{Ne}}{RT}=\frac{3.6atm*4.5L}{0.082\frac{atm*L}{mol*K}*298.15K}=0.663molNe$

Now, one considers the total moles (addition between both neon's and helium's moles) and the total volume to compute the final pressure as shown below:

$P=\frac{n_TRT}{V_T} =\frac{(0.688+0.663)mol*0.082\frac{atm*L}{mol*K}*298.15K}{9.0L}=3.7atm$

Best regards.

8 0

3 years ago

Which geologic time did humans exist

umka2103 [35]

Answer:

B

Explanation:

because its says mesozoic era

4 0

3 years ago

Read 2 more answers