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3 years ago

7. How many significant figures are in the following numbers?

Chemistry

1 answer:

Vlad1618 [11]3 years ago

7 0

There are
A. 6 significant figures
B.5 sig figs
C.2 sig figs
D.5 sig figs

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Is the bond C=O polar or non polar

rewona [7]

Answer:

Non Polar

Explanation:

Non Polar molecule because of its linear symmetric shape

6 0

3 years ago

5) How many moles are in 5 Liters of H2 gas?

telo118 [61]

From 5 L to moles, just divide 5 by 22.4. I got 0.22 moles of H2.
From 5 moles to liters, just multiply 5 by 22.4. I got 112 L of H2.

4 0

3 years ago

20cm of 0.09M solution of H2SO4. requires 30cm of NaOH for complete neutralization. Calculate the

kirill115 [55]

Answer:

Choice A: approximately $0.12\; \rm M$ .

Explanation:

Note that the unit of concentration, $\rm M$ , typically refers to moles per liter (that is: $1\; \rm M = 1\; \rm mol\cdot L^{-1}$ .)

On the other hand, the volume of the two solutions in this question are apparently given in $\rm cm^3$ , which is the same as $\rm mL$ (that is: $1\; \rm cm^{3} = 1\; \rm mL$ .) Convert the unit of volume to liters:

$V(\mathrm{H_2SO_4}) = 20\; \rm cm^{3} = 20 \times 10^{-3}\; \rm L = 0.02\; \rm L$ .
$V(\mathrm{NaOH}) = 30\; \rm cm^{3} = 30 \times 10^{-3}\; \rm L = 0.03\; \rm L$ .

Calculate the number of moles of $\rm H_2SO_4$ formula units in that $0.02\; \rm L$ of the $0.09\; \rm M$ solution:

$\begin{aligned}n(\mathrm{H_2SO_4}) &= c(\mathrm{H_2SO_4}) \cdot V(\mathrm{H_2SO_4})\\ &= 0.02 \; \rm L \times 0.09 \; \rm mol\cdot L^{-1} = 0.0018\; \rm mol \end{aligned}$ .

Note that $\rm H_2SO_4$ (sulfuric acid) is a diprotic acid. When one mole of $\rm H_2SO_4$ completely dissolves in water, two moles of $\rm H^{+}$ ions will be released.

On the other hand, $\rm NaOH$ (sodium hydroxide) is a monoprotic base. When one mole of $\rm NaOH$ formula units completely dissolve in water, only one mole of $\rm OH^{-}$ ions will be released.

$\rm H^{+}$ ions and $\rm OH^{-}$ ions neutralize each other at a one-to-one ratio. Therefore, when one mole of the diprotic acid $\rm H_2SO_4$ dissolves in water completely, it will take two moles of $\rm OH^{-}$ to neutralize that two moles of $\rm H^{+}$ produced. On the other hand, two moles formula units of the monoprotic base $\rm NaOH$ will be required to produce that two moles of $\rm OH^{-}$ . Therefore, $\rm NaOH$ and $\rm H_2SO_4$ formula units would neutralize each other at a two-to-one ratio.

$\rm H_2SO_4 + 2\; NaOH \to Na_2SO_4 + 2\; H_2O$ .

$\displaystyle \frac{n(\mathrm{NaOH})}{n(\mathrm{H_2SO_4})} = \frac{2}{1} = 2$ .

Previous calculations show that $0.0018\; \rm mol$ of $\rm H_2SO_4$ was produced. Calculate the number of moles of $\rm NaOH$ formula units required to neutralize that

$\begin{aligned}n(\mathrm{NaOH}) &= \frac{n(\mathrm{NaOH})}{n(\mathrm{H_2SO_4})}\cdot n(\mathrm{H_2SO_4}) \\&= 2 \times 0.0018\; \rm mol = 0.0036\; \rm mol\end{aligned}$ .

Calculate the concentration of a $0.03\; \rm L$ solution that contains exactly $0.0036\; \rm mol$ of $\rm NaOH$ formula units:

$\begin{aligned}c(\mathrm{NaOH}) &= \frac{n(\mathrm{NaOH})}{V(\mathrm{NaOH})} = \frac{0.0036\; \rm mol}{0.03\; \rm L} = 0.12\; \rm mol \cdot L^{-1}\end{aligned}$ .

3 0

3 years ago

Name the covalent compound:<br><br> I8P

SOVA2 [1]

There are certain rules to follow when naming covalent compounds. But first, let us look at the definition of Covalent Compounds.

<h3>What are Covalent Compounds?</h3>

When covalent bonds aid the creation of a molecule, in which the atoms have at least one similar pair of valence electrons, a covalent compound is said to have been formed.

A very common example is water (H₂O)

<h3>How are Covalent Compounds named?</h3>

To name a covalent compound, simply list the first element in the formula using the name of the element, then name the second element by adding the suffix "ide" to the stem of the second element's name.

If there is only one atom in the molecule of the first element, then no prefix should be added.

It is to be noted that if the second element in the compound is oxygen, then we should say:

monox<em>ide</em> instead of monoox<em>ide</em> and
triox<em>ide</em> instead of trox<em>ide</em>, all depending on how many atoms that are involved.

See the attached for the prefixes related to the various number of atoms in the compounds.

It is to be noted that the covalent compound to be named here is not stated hence the general answer.

Learn more about naming covalent compounds at:
brainly.com/question/9841865

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6 0

1 year ago

¿Podría predecir con antelación si una disolución acuosa será buena conductora de la corriente eléctrica, sabiendo cuál es el so

Ne4ueva [31]

Answer:

Si.

Explicación:

Sí, podemos predecir si una solución acuosa será un buen conductor de corriente eléctrica si conocemos el soluto que se disuelve en ese líquido y su concentración o cantidad. Hay algunas sustancias que se ionizan cuando se agregan en un líquido como el agua. Debido a esta ionización, será un buen conductor de electricidad. Por ejemplo, la adición de una gran cantidad de cloruro de sodio en agua ioniza y hace que el agua sea un buen medio conductor de electricidad.

3 0

3 years ago