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Sladkaya [172]
3 years ago
8

The diagram shows the box for an element in the periodic

Chemistry
1 answer:
mr_godi [17]3 years ago
6 0

Answer: A 13

Explanation: hope this helps!

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A steel tank contains carbon dioxide at a pressure of 13.0 atm when the temperature is 34oC. What will be the internal gas press
morpeh [17]

Answer:

D. 15.8atm

Explanation:

Given parameters:

Initial pressure = 13atm

Initial temperature  = 34°C = 34 + 273  = 307K

Final temperature  = 100°C = 100 + 273  = 373K

Unknown:

Final pressure  = ?

Solution:

To solve this problem, we apply a derivation of the combined gas law taking the volume as a constant.

The expression is shown mathematically below;

        \frac{P_{1} }{T_{1} }   = \frac{P_{2} }{T_{2} }

P and T pressure and temperature values

1 and 2 are initial and final states

 Insert the parameters and solve for T₂;

    \frac{13}{307}   = \frac{P_{2} }{373}  

        P₂  = 15.8atm

4 0
3 years ago
The products of photosynthesis are the starting materials of cellular respiration true or false
notsponge [240]

True....

Explanation

Cells use oxygen to release energy during photosynthesis/chlorophyll/cellular respiration. For photosynthesis, the starting materials are water and carbon dioxide, and the products are sugar and oxygen. For cellular respiration, the starting materials are oxygen and sugar, and the products are carbon dioxide and water.

4 0
2 years ago
what is the effect of using higher concentration of sodium hydrogen carbonate on the rate of reaction?
Alex
Increasing the concentration of one or more reactants will often increase the rate of reaction. This occurs because a higher concentration of a reactant will lead to more collisions of that reactant in a specific time period.

Reaction rate increases with concentration, as described by the rate law and explained by collision theory. As reactant concentration increases, the frequency of collision increases. The rate of gaseous reactions increases with pressure, which is, in fact, equivalent to an increase in concentration of the gas.
7 0
2 years ago
Hard water often contains dissolved Ca2+ and Mg2+ ions. One way to soften water is to add phosphates. The phosphate ion forms in
avanturin [10]
<span>5.5×10−2M in calcium chloride and 8.0×10−2M in magnesium nitrate.
What mass of sodium phosphate must be added to 1.5L of this solution to completely eliminate the hard water ion

1) Content of Ca (2+) ions

Calcium chloride = CaCl2

Ionization equation: CaCl2 ---> Ca (2+) + 2 Cl (-)

=> Molar ratios: 1 mol of CaCl2 : 1 mol Ca(2+) : 2 mol Cl(-)

Calculate the number of moles of CaCl2 in 1.5 liters of 5.5 * 10^-2 M solution

M = n / V => n = M*V = 5.5 * 10^ -2 M * 1.5 l = 0.0825 mol CaCl2

=> 0.0825 mol Ca(2+)

2) Number of phosphate ions needed to react with 0.0825 mol Ca(2+)

formula of phospahte ion: PO4 (3-)

molar ratio: 2PO4(3-) + 3Ca(2+) = Ca3 (PO4)2

Proportion: 2 mol PO4(3-) / 3 mol Ca(2+) = x / 0.0825 mol Ca(2+)

=> x = 0.0825 coml Ca(2+) * 2 mol PO4(3-) / 3 mol Ca(2+) = 0.055 mol PO4(3-)

3) Content of Mg(2+) ions

Ionization equation: Mg (NO3)2 ----> Mg(2+) + 2 NO3 (-)

Molar ratios: 1 mol Mg(NO3)2 : 1 mol Mg(2+) + 2 mol NO3(-)

number of moles of Mg(NO3)2 in 1.5 liter of 8.0 * 10^-2 M solution

n = M * V = 8.0 * 10^ -2 M * 1.5 liter = 0.12 moles Mg(NO3)2

ions of Mg(2+) = 0.12 mol Mg(NO3)2 * 1 mol Mg(2+) / mol Mg(NO3)2 = 0.12 mol Mg(2+)

4) Number of phosphate ions needed to react with 0.12 mol Mg(2+)

2PO4(3-) + 3Mg(2+) = Mg3(PO4)2

=> 2 mol PO4(3-) / 3 mol Mg(2+) = x / 0.12 mol Mg(2+)

=> x = 0.12 * 2/3 mol PO4(3-) = 0.16 mol PO4(3-)

5) Total number of moles of PO4(3-)

0.055 mol + 0.16 mol = 0.215 mol

6) Sodium phosphate

Sodium phosphate = Na3(PO4)

Na3PO4 ---> 3Na(+) + PO4(3-)

=> 1 mol Na3PO4 : 1 mol PO4(3-)

=> 0.215 mol PO4(3-) : 0.215 mol Na3PO4

mass in grams = number of moles * molar mass

molar mass of Na3 PO4 = 3*23 g/mol + 31 g/mol + 4*16 g/mol = 164 g/mol

=> mass in grams = 0.215 mol * 164 g/mol = 35.26 g

Answer: 35.26 g of sodium phosphate
</span>
5 0
3 years ago
Create a food chain that shows the energy transfer from the sun to a grizzly bear. Include four transitions (arrows) in your foo
lidiya [134]

Sun⇒ Phytoplankton (Producer)⇒ Zooplankton (Primary consumer)⇒ Fish (Secondary consumer)⇒ Bear (Tertiary consumer).

  • A food chain is a sequence of transfer of food and energy when one organism is consumed by another organism.
  • A food chain is always unidirectional sequence.
  • In the provided food chain the sun is the source of energy required for the preparation of food by the phytoplankton that is an aquatic autotroph which will prepare its food by the process of photosynthesis.
  • The phytoplankton being producer of biomass is consumed by the zooplankton that is the primary consumer than the zooplankton will be consumed by the fish that is the secondary consumer and carnivore by origin and finally the fish will be consumed by the bear that is also carnivore and is tertiary consumer.

Learn more about food chain:

brainly.com/question/16543685

6 0
2 years ago
Read 2 more answers
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