How many atoms of each element are present in

Please help if you can help me, you can have all my points and be brainlest!

brilliants [131]

Answer:

Erosion by water

Explanation:

Moving water carrying away small pieces of rock is erosion by water.

E.g when the sea hits on the cliff and then takes away the fragments with it

Hope I helped

5 0

3 years ago

Why do elements in a group on the periodic table have similar chemical properties?

NARA [144]

Do elements in a group on the periodic table have similar chemical properties because their atoms have the same number of electrons

A. same number of outermost electrons

6 0

4 years ago

What is the ph of a 0.500 m solution of benzoic acid, pka = 4.19?

oksian1 [2.3K]

Solution:

Benzoic acid is C6H5COOH

In finding pH

C6H5COOH(aq) <=> C6H5COO^- + H^+ pKa = 4.19, pKa = -logKa so Ka = 10^(-4.19)

Ka = 6.45 x 10^-6

[C6H5COO^-] = x = [H^+]; [C6H5COOH] = 0.5 - x (we are able to make an estimate of [C6H5COOH] = 0.5.

Ka = [H^+][C6H5COO^-]/[C6H5COOH] = x^2/(0.5 - x) = 6.45 x 10^-6

Now,

According to the quadratic equation. x^2 = 3.23 x 10^-5 - 6.45 x 10^-6x

x^2 + (6.45 x 10^-6)x - 3.23 x 10^-5 = 0

enter a = 1, b = 0.00000645, c = 0.0000323

x = 5.68 x 10^-3 = 0.00568 M expression is [C6H5COOH] = 0.5 M is the correct answer.

[H^+] = 0.00568 M, so pH = -log(0.00568 M ) = 2.25

This is the required solution.

7 0

4 years ago

What Household item turns electrical energy into radiant energy

luda_lava [24]

Answer:

Lamps and televisions

Explanation:

I think those qualify.

6 0

3 years ago

Read 2 more answers

I need some help with a long chemistry problem. Anything is appreciated!

Mkey [24]

Answer:

The CSI is wrong.

Explanation:

1. Find the volume of the pool

The formula for the volume of a cylinder is V = πr²h .

D = 12 m; h = 10 m

r = D/2 = (12 m/2) = 6.0 m

V = πr²h = π × (6.0 m)² × 10 m = π × 36 m²× 10 m = 360π m³ = 1100 m³

= 1.1. × 10⁶ L

2. Calculate the moles of OH⁻

n = cV = 1.0 × 10⁻² mol·L⁻¹ × 1.3 × 10⁶ L = 11 000 mol of OH⁻

3. Calculate the moles of acetic acid needed for neutralization

HA + OH⁻ ⟶ A⁻ + H₂O

The molar ratio of is 1 mol HA:1 mol OH⁻, so you need 11 000 moL of acetic acid.

4. Calculate the actual moles of acetic acid

You have four 5 L jugs of acetic acid pH 2 .

Volume = 20 L

[H⁺] = 10⁻² mol·L⁻¹ = 0.01 mol·L⁻¹

(a) Set up an ICE table

HA + H₂O ⇌ A⁻ + H₃O⁺

I/mol·L⁻¹: c 0 0

I/mol·L⁻¹: - 0.01 +0.01 +0.01

I/mol·L⁻¹: c - 0.01 0.01 0.01

$K_{\text{a}} = \dfrac{\text{[A]}^{-}\text{[H$_{3}$O$^{+}$]}}{\text{[HA]}} = 1.76 \times 10^{-5}$

(b) Calculate the concentration of acetic acid

$\begin{array}{rcl}\dfrac{\text{[A]}^{-}\text{[H$_{3}$O$^{+}$]}}{\text{[HA]}}& = & 1.76 \times 10^{-5}\\\\\dfrac{0.01\times 0.01}{c}& = & 1.76 \times 10^{-5}\\\\1 \times 10^{-4} & = & 1.76 \times 10^{-5}c\\c & = & \dfrac{1 \times 10^{-4}}{1.76 \times 10^{-5}}\\\\ & = & \text{6 mol/L}\\\end{array}$

The concentration of the acetic acid is 6 mol·L⁻¹

(c) Calculate the moles of acetic acid

$n = \text{20 L} \times \dfrac{\text{6 mol}}{\text{1 L}} = \textbf{100 mol}$

You have 100 mol of acetic acid.

The CSI is wrong.

You don't have enough acetic acid to neutralize the pool.

8 0

4 years ago