How many neutrons are in an atom with atomic number of 53 and mass number of 127?

6 Fe2+ (aq) + Cr2O72− (aq) + 14 H+ (aq) → 6 Fe3+ (aq) + 2 Cr3+ (aq) + 7 H2O (aq) If the titration of 23 mL of an iron(II) soluti

ratelena [41]

Answer:

1.047 M

Explanation:

The given reaction:

$6Fe^{2+}_{(aq)}+Cr_2O_7^{2-}_{(aq)}+14H^+_{(aq)}\rightarrow 6Fe^{3+}_{(aq)}+2Cr^{3+}_{(aq)}+7H_2O_{(aq)}$

For dichromate :

Molarity = 0.254 M

Volume = 15.8 mL

The conversion of mL to L is shown below:

1 mL = 10⁻³ L

Thus, volume = 15.8 ×10⁻³ L

Thus, moles of dichromate :

$Moles=0.254 \times {15.8\times 10^{-3}}\ moles$

Moles of dichromate = 0.0040132 moles

1 mole of dichromate react with 6 moles of iron(II) solution

Thus,

0.0040132 moles of dichromate react with 6 × 0.0040132 moles of iron(II) solution

Moles of iron(II) solution = 0.02408 moles

Volume = 23 mL = 0.023 L

Considering:

$Molarity=\frac{Moles\ of\ solute}{Volume\ of\ the\ solution}$

<u>Molarity = 0.02408 / 0.023 = 1.047 M</u>

7 0

3 years ago

Cloudy nights can be warmer than clear nights because clouds trap heat

tigry1 [53]

Answer:

Cloudy nights can be warmer than clear nights because clouds trap heat absorbed by Earth during daylight hours.

4 0

3 years ago

Read 2 more answers

If I have 12 protons, how many neutrons and electrons would I need to make a stable atom?

lesantik [10]

Answer:

im pretty sure you need 15 in all but dont get mad it thats wrong, so you would i think need 3 neutrons

Explanation:

3 0

3 years ago

extremely hot.When a student went to open the car doo , he burned his finger. What two forms of energy were responsible for the

charle [14.2K]

Answer:

radiation and conduction

Explanation:

During a warm summer day, a car became extremely hot. When a student went to open the car door, he burned his fingers. What two forms of energy were responsible for the student burning his fingers?

Solution:

Heat is the transfer of energy from a warmer object to a cooler object. For heat transfer to occur, there have to be a difference in temperature between two objects.

Heat can be transferred in three ways: by conduction, by convection, and by radiation.

Conduction is the transfer of thermal energy between bodies through direct contact. Convection is the transfer of thermal energy through the movement of heat in a liquid or gas. Radiation is the transfer of thermal energy through thermal emission by electromagnetic waves.

During a warm summer day, The sun makes the car to become hot through energy transfer from the sun to the car. When the student touch the car, there is heat transfer as a result of conduction.

3 0

3 years ago

Consider the nuclear equation below. Superscript 235 subscript 92 upper U right arrow superscript 4 subscript 2 upper H e. What

coldgirl [10]

Answer:

$\rm_{90}^{231}\text{Th}$

Explanation:

The unbalanced nuclear equation is

$\rm _{92}^{235}\text{U} \longrightarrow \, _{2}^{4}\text{He} + X$

Let's write X as a nuclear symbol.

$\rm _{92}^{235}\text{U} \longrightarrow \, _{2}^{4}\text{He} + _{Z}^{A}\text{X}$

The main point to remember in balancing nuclear equations is that the sums of the superscripts and of the subscripts must be the same on each side of the reaction arrow.

Then

235 = 4 + A , so A = 235 - 4 = 231, and

92 = 2 + Z , so Z = 92 - 2 = 90

And your nuclear equation becomes

$\rm _{92}^{235}\text{U} \longrightarrow \, _{2}^{4}\text{He} +\, _{90}^{231}\text{X}$

Element 90 is thorium, so

$\rm X = _{90}^{231}\text{Th}$

7 0

3 years ago