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zhenek [66]
3 years ago
15

What are elements represented by ?

Chemistry
1 answer:
makvit [3.9K]3 years ago
4 0

A Chemical Symbol

need 20 characters

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A student needs to convert a volume of 3 Tbsp (tablespoons) to mL. The student finds out that 1 tablespoon is equivalent to 14.7
garri49 [273]

Answer:

The conversion factor is 14.79 mL/Tbsp.

Explanation:

To do an unity conversiton, we can make a factor by a ratio transformation:

3 Tbsp * \frac{14.79 mL}{1Tbsp}

So, the conversion factor is 14.79 mL/Tbsp and 3 Tbsp has 44.37 mL.

3 0
3 years ago
During the formation of a chemical bond between two hydrogen atoms, which of the following statements is always true?
Wewaii [24]

A) Energy is released during the formation of the bond.

Explanation:

During the formation of a chemical bonds between two hydrogen atoms, energy is always released during the formation of this bond type.

Bond formation process is usually exothermic and energy is released during the formation of the bond.

  • Bond breaking process is an endothermic process in which energy is absorbed from the surrounding.
  • Whenever a bond is broken, the bond energy value is positive but when a bond is formed, the bond energy value is given a negative sign.

For a bond formation process in which hydrogen atoms are bonded covalently, energy is usually released.

Learn more:

Enthalpy changes brainly.com/question/10567109

#learnwithBrainly

5 0
3 years ago
5. Which of these elements has the greatest atomic radius? *<br> Be<br> Mg<br> Ra<br> Ba
trapecia [35]
The answer is Ra
Atomic number for Be is 4

Atomic number for Mg 12

Atomic number for Ra 88

Atomic number for Ba 56
5 0
3 years ago
A 25.0-mL sample of 0.150 M hydrazoic acid, HN3, is titrated with a 0.150 M NaOH solution. What is the pH after 13.3 mL of base
tamaranim1 [39]

Answer:

pH ≅ 4.80

Explanation:

Given that:

the volume of HN₃ = 25 mL = 0.025 L

Molarity of HN₃ = 0.150 M

number of moles of HN₃ = 0.025 × 0.150

number of moles of HN₃ =  0.00375  mol

Molarity of NaOH = 0.150 M

the volume of NaOH = 13.3 mL = 0.0133

number of moles of NaOH = 0.0133× 0.150

number of moles of NaOH = 0.001995 mol

The chemical equation for the reaction of this process can be written as:

HN_3 + OH- ---> N^-_{3} + H_2O

1 mole of hydrazoic acid react with 1 mole of hydroxide to give nitride ion and water

thus the new number of moles of HN₃ = 0.00375 - 0.001995 = 0.001755 mol

Total volume used in the reaction =  0.025 +  0.0133 = 0.0383  L

Concentration of HN_3 = \dfrac{0.001755}{0.0383} = 0.0458 M

Concentration of N^{-}_3 = \dfrac{ 0.001995 }{0.0383} = 0.0521 M

GIven that :

Ka = 1.9 x 10^{-5}

Thus; it's pKa = 4.72

pH =4.72 +  log(\dfrac{ \ 0.0521}{0.0458})

pH =4.72 + log(1.1376)

pH =4.72 + 0.05598

pH =4.77598

pH ≅ 4.80

3 0
3 years ago
how many grams of solid lithium must be added to liquid after in order to obtain 15.0 L of hydrogen gas at STP?
alexdok [17]

Answer:

9.29g

Explanation:

your welcome

3 0
3 years ago
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