PLEASE HELP!!!!<br> Balance the equation<br> (Image below)

What type of ion do elements from each of the following groups form ,<br> group1 <br> group 7.

Artemon [7]

Answer:

group 1 - cations charge +1

group 7 - anions charge -1

Explanation:

Group 1 has one valence electron and will lose one electron to complete the octet.

Group 7 has 7 valence electrons and will accept an electron to complete the octet.

7 0

3 years ago

A solution is made containing 4.6 g of sodium chloride per 250g of water.

lozanna [386]

Answer:

$\large \boxed{1.81 \, \%}$

Explanation:

$\text{Mass percent} = \dfrac{\text{mass of solute} }{\text{mass of solution}} \times 100 \, \%$

Data:

Mass of NaCl = 4.6 g

Mass of water = 250 g

Calculations:

Mass of solution = mass of NaCl + mass of water = 4.6 g + 250 g = 254.6 g.

$\text{\% m/m} = \dfrac{\text{4.6 g} }{\text{254.6 g}} \times 100 \, \% = \mathbf{1.81 \, \%}\\\\\text{The percent by mass of NaCl is $\large \boxed{\mathbf{1.81 \, \%}}$}$

3 0

3 years ago

a compound containing only carbon and hydrogen produces 1.80 gCO2 and 0.738 gH2O. Find the empirical formula of the compound. Ex

r-ruslan [8.4K]

Answer:

The empirical formula is CH2

Explanation:

Step 1: Data given

Mass of CO2 produced = 1.80 grams

Mass of H2O produced = 0.738 grams

Step 2: The balanced equation

CxHy + O2 → CO2 + H2O

Step 3: Calculate moles CO2

Moles CO2 = mass CO2 / molar mass CO2

Moles CO2 = 1.80 grams / 44.01 g/mol

Moles CO2 = 0.0409 moles

Step 4: Calculate moles C

In 1 mol CO2 we have 1 mol CO2

In 0.0409 moles CO2 we have 0.0409 mol C

Step 5: Calculate moles H2O

Moles H2O = mass H2O / molar mass H2O

Moles H2O = 0.738 grams / 18.02 g/mol

Moles H2O = 0.04095 moles

Step 6: Calculate moles H

In 1 mol H2O we have 2 moles H

In 0.04095 moles H2O we have 2*0.04095 = 0.0819 moles H

Step 7: Calculate the mol ratio

We divide by the smallest amount of moles

C: 0.0409 / 0.0409 = 1

H: 0.0819 moles / 0.0409 = 2

The empirical formula is CH2

4 0

3 years ago

When 0.5141 g of biphenyl (C12H10) undergoes combustion in a bomb calorimeter, the temperature rises from 25.823 °C to 29.419 °C

natka813 [3]

Answer:

$\Delta_{r}U$ of the reaction is -6313 kJ/mol

$\Delta_{r}H$ of the reaction is -6312 kJ/mol

Explanation:

$Temperature\,\,change= \Delta U = 29.419-25.823 =3.506^{o}C$

$q_{cal}= C \times \Delta T$

$=5.861 \times 3.596 = 21.076\,kJ$

$q_{rxn}= -q_{cal}= -21.076\,kJ$

$\Delta_{r}U= -21.076 \times \frac{154}{0.5141}= -6313\, kJ/mol$

Therefore, $\Delta_{r}U$ of the reaction is -6313 kJ/mol.

The chemical reaction in bomb calorimeter is as follows.

$C_{12}H_{10}(s)+\frac{27}{2}O_{2}(g)\rightarrow 12CO_{2}(g)+5H_{2}O(g)$

$Number\,of\,moles\Delta n=(12+5)-\frac{27}{2}=3.5$

$\Delta_{r}H=\Delta E+ \Delta n. RT$

$=-6313+3.5\times 8.314\times 10^{-3} \times 3.596=-6312\,kJ/mol$

Therefore, $\Delta_{r}H$ of the reaction is -6312 kJ/mol.

3 0

3 years ago

Fermium-253 has a half-life of 0.334 seconds. How long will it take, in seconds, for a 96 atom sample to decay to 3 atoms?

iris [78.8K]

Answer:3.34 seconds

Explanation:

8 0

3 years ago

PLEASE HELP!!!! Balance the equation (Image below)