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2 years ago

Please, please someone answer. Chem isn't my strong suit.

Chemistry

1 answer:

Yuki888 [10]2 years ago

5 0

U-238 has 92 protons, 146 neutrons, and 92 electrons.
Rn-222 has 86 protons, 136 neutrons, and 86 electrons.

U-238 is Uranium 238 and Rn-222 is Radon 222.

You might be interested in

What is the empirical formula for a compound if a sample contains 3.72 g of P and 21.28 g of Cl

fenix001 [56]

M(P)=3.72 g
M(P)=31 g/mol

m(Cl)=21.28 g
M(Cl)=35.5 g/mol

n(P)=m(P)/M(P)
n(P)=3.72/31=0.12 mol

n(Cl)=m(Cl)/M(Cl)
n(Cl)=21.28/35.5=0.60 mol

P : Cl = 0.12 : 0.60 = 1 : 5

PCl₅ - is the empirical formula

6 0

3 years ago

How can equilibrium of a closed system chemical reaction be disturbed? Select all that apply.

charle [14.2K]

The correct answers are :

Changing the volume of the system.

Changing the temperature of the system.

Equilibrium will remain unaffected if the concentration of products and reactants are kept the same, and the temperature of the system is kept constant.

As the system is closed, we cannot add or remove products or reactants.

Change in temperature will shift the chemical equilibrium towards the reactant or product depending on whether the reaction is exothermic or endothermic.

Also change in volume will shift the chemical equilibrium of a chemical reaction if the reactants or products or both are gases.

8 0

3 years ago

Read 2 more answers

When water freezes into ice, sme of the properties have changed <br> What stays the same

larisa86 [58]

When water freezes into ice, some of the properties have change. What stays the same.

Answer: 1: Ice Melting is a physical change. When liquid water (H2O) freezes into a solid state (ice), it appears changed; However, this change is only physical as the the composition of the constituent molecules is the same: 11.19% hydrogen and 88.81% oxygen by mass.

Have a goood day!

5 0

2 years ago

When 7.085 grams of a hydrocarbon, CxHy, were burned in a combustion analysis apparatus, 21.71 grams of CO2 and 10.37 grams of H

Taya2010 [7]

Answer:

- Empirical:

$C_3H_7$

- Molecular:

$C_6H_{14}$

Explanation:

Hello,

In this case, based on the information regarding the combustion, the moles of carbon turn out:

$n_C=21.71gCO_2*\frac{1molCO_2}{44gCO_2}*\frac{1molC}{1molCO_2}=0.493molC$

Moreover, the moles of hydrogen:

$n_H=10.37gH_2O*\frac{1molH_2O}{18gH_2O}*\frac{2molH}{1molH_2O}=1.152molH$

Thus, the subscripts of carbon and hydrogen in the hydrocarbon turn out:

$C=\frac{0.4934}{0.4934}=1\\H=\frac{1.15222}{0.4934}=2.335\\CH_{2.335}$

Now, looking for a suitable whole number we obtain the following empirical formula as 2.335 times 3 is 7 for hydrogen:

$C_3H_7$

In such a way, that compound has a molar mass of 43 g/mol, thus, the whole compound's molar mass is 86.18 g/mol for which the molecular formula is twice the empirical one, therefore:

$C_6H_{14}$

Which is hexane.

Best regards.

6 0

3 years ago

What is the chemical formula for a compound between Li and Br?

natima [27]

LiBr.

<h3>Explanation</h3>

Note that the group number in this answer refers to the new IUPAC group number, which ranges from 1 to 18. Counts from the left. Start with the first two column (group 1 and 2), go on to the transition elements (Sc, Ti, etc. in group 3 through 12), and continue with the nonmetals (group 13 through 18).

Li is a group 1 metal. As a metal, it tends to form positive ions ("cations"). Metals in group 1 and 2 are <em>main group</em> metals. The charge on main group metal ions tends to be the same as the group number of the metal. Li is in group 1. The charge on an Li ion will be +1. Formula of the Li ion will be $\text{Li}^{+}$ .

Br is a group 17 nonmetal. As a nonmetal, it tends to form negative ions ("anions"). The charge on nonmetal ions excepting for H tends to equal the group number of the nonmetal minus 18. Br is in group 17. The charge on a Br ion will be 17 - 18 = -1. Formula of the Br ion will be $\text{Br}^{-}$

All the ions in an ionic compound carry charge. However, some of the ions like $\text{Li}^+$ are positive. Others ions like $\text{Br}^{-}$ are negative. Charge on the two types of ions balance each other. As a result, the compound is <em>overall</em> neutral.

1 × (+1) + 1 × (-1) = 0. The positive charge on one $\text{Li}^{+}$ ion balances the negative charge on one $\text{Br}^{-}$ ion. The two ions would pair up at a 1:1 ratio.

The empirical formula for an ionic compound shows all the ions in the compound. Positive ions are written in front of negative ions. $\text{Li}^{+}$ is positive and $\text{Br}^{-}$ is negative. The formula shall also show the simplest ratio between the ions. For the compound between Li and Br, a 1:1 ratio will be the simplest. The "1" subscript in an empirical formula can be omitted. Hence the formula: LiBr.

5 0

3 years ago