The correct electron configuration is....

Please help I will give brainiest

weeeeeb [17]

Answer:

1. Least

2. Most

3 0

3 years ago

Read 2 more answers

According to dalton, if 2 grams of element xcombine with 4 grams of element yto form compound xy, how many grams of element xwou

Evgen [1.6K]

14g of element x is the answer.

3 0

3 years ago

Which of the following statements about natural resources is correct

trasher [3.6K]

Answer:

The right choice is "wind power requires a lot of space and depends on local weather patterns "

Explanation:

solar power produces harmful chemicals

it is incorrect because solar power doesn't produce any chemicals

2. geothermal power requires more land than other power plants

it is incorrect because geothermal power requires digging a stable 5 km-deep shaft not a land

3. nuclear power produces small amounts of energy from large masses

it is incorrect because nuclear power produces large amounts of energy from small masses.

So the right choice is "wind power requires a lot of space and depends on local weather patterns "

7 0

3 years ago

Tris is a weak base. The basic form of tris can be written tris0 and the protonated (conjugate acid) form can be written tris. T

Arada [10]

Answer:

a) [Tris0] : [Tris] = 1 : 100

b) Range = 7.1 to 9.1

Explanation:

a) Calculation of ratio of the basic and the acidic forms of tris

pH of a buffer is calculate using Henderson-Hasselbalch equation

$pH = pKa+log\frac{Salt}{Acid}$

Conjugate acid of Tris dissociated as

$Tris \leftrightharpoons Tris0 + H^+$

For tris,

Salt or Basic form = tris0

Acid or Acidic form = Tris

pKa = 8.1

pH = 6.1

$pH = pKa+log\frac{Tris0}{Tris}$

$6.1 = 8.1+log\frac{Tris0}{Tris}$

$log\frac{Tris0}{Tris} = -2$

$\frac{Tris0}{Tris} = antilog (-2)$

$\frac{Tris0}{Tris} = 10^{-2}$

[Tris0] : [Tris] = 1 : 100

b) Range of Tris

Range of any buffer is:

From (pKa -1) to (pKa+1)

So, range of Tris is:

From (8.1 - 1) to (8.1 +1)

or from 7.1 to 9.1

8 0

3 years ago

Natural gas burns in air to form carbon dioxide and water, releasing heat. CH4(g)+2O2(g)→CO2(g)+2H2O(g) ΔHrxn = -802.3 kJ.

Olenka [21]

Answer:

1) Minimum mass of methane required to heat 45.0 g of water by 21.0°C is 0.0788 g.

2) Minimum mass of methane required to heat 50.0 g of water by 26.0°C is 0.108 g.

Explanation:

$CH_4(g)+2O_2(g)\rightarrow CO_2(g)+2H_2O(g) ,\Delta H_{rxn} =-802.3 kJ$

1) Minimum mass of methane required to raise the temperature of water by 21.0°C.

Mass of water = m = 45.0 g

Specific heat capacity of water = c = 4.18 J/g°C

Change in temperature of water = ΔT = 21.0°C.

Heat required to raise the temperature of water by 21.0°C = Q

$Q=mc\Delta T= 45.0 g\times 4.18 J/g^oC\times 21.0^oC$

Q = 3,950.1 J = 3.9501 kJ

According to reaction 1 mole of methane on combustion gives 802.3 kJ of heat.

Then 3.950.1 kJ of heat will be given by:

$=\frac{3.950.1 kJ}{802.3 kJ}=0.004923 mol$

Mass of 0.004923 moles of methane :

0.004923 mol × 16 g/mol=0.0788 g

Minimum mass of methane required to heat 45.0 g of water by 21.0°C is 0.0788 g.

2) Minimum mass of methane required to raise the temperature of water by 26.0°C.

Mass of water = m = 50.0 g

Specific heat capacity of water = c = 4.18 J/g°C

Change in temperature of water = ΔT = 26.0°C.

Heat required to raise the temperature of water by 21.0°C = Q

$Q=mc\Delta T= 50.0 g\times 4.18 J/g^oC\times 26.0^oC$

Q = 5,434 J= 5.434 kJ

According to reaction 1 mole of methane on combustion gives 802.3 kJ of heat.

Then 5.434 kJ of heat will be given by:

$=\frac{5.434 kJ}{802.3 kJ}=0.006773 mol$

Mass of 0.006773 moles of methane :

0.006773 mol × 16 g/mol= 0.108 g

Minimum mass of methane required to heat 50.0 g of water by 26.0°C is 0.108 g.

6 0

4 years ago