How can you describe the location of hafnium on the periodic table? Choose all that apply.

An aqueous solution at 25.0°C contains [H+] = 0.075 M. What is the pH of the solution?

olasank [31]

Answer:

1.131

Explanation:

pH=-logH^+

H^+=0.074

pH=-log 0.074

pH=1.131

7 0

3 years ago

Why is burning fossil fuels negative

Likurg_2 [28]

Answer:

it causes alot of harm to the earth.

Explanation:

earthquakes

an so on

5 0

4 years ago

Which of the following is an acid-base neutralization reaction? (1 point) Sn + 2HBr yields SnBr2 + H2 HCl + KOH yields KCl + H2O

borishaifa [10]

Answer:

Explanation:

Sn + 2HBr = SnBr₂ + H₂

Here HBr is an acid but Sn is not a base . It is a metal . So it is not an acid - base reaction .

HCl + KOH = KCl + H₂O

HCl is an acid and KOH is a base so it is an acid base reaction.

2AlCl₃ + 3Ca(OH)₂ = 2Al(OH)₃ + 3CaCl₂

It is an acid base reaction . It is so because aluminium hydroxide is a lewis acid and calcium hydroxide is a base . So it is an acid base reaction .

2C₂H₆ +7O₂ = 4CO₂ + 6H₂O

It is not an acid base reaction . It is actually an example of oxidation reaction in which ethane burns in oxygen to give carbon dioxide and water.

5 0

3 years ago

German physicist Werner Heisenberg related the uncertainty of an object\'s position (Δx) to the uncertainty in its velocity Δv.

Assoli18 [71]

Heisenberg's Uncertainty Principle gives a relationship between the standard deviation of an object's position and its momentum.

$\Delta p \cdot \Delta x = h / (4 \pi)$ where

$\Delta p$ the standard deviation of the object's momentum,
$\Delta x$ the standard deviation of the object's position, and
$h \approx 6.63 \times 10^{-34} \; \text{J} \cdot \text{s}$ the Planck's constant.

By definition, the momentum of the electron equals the product of its mass and velocity.

$p = m\cdot v$

Assuming that measurement of the mass of the electron $m$ is accurate. It is assumed to be a coefficient of constant value. The standard deviation in the electron's velocity is thus directly related to that of its mass. That is:

$\Delta p = m \cdot \Delta v$

$\Delta v = 0.01 \times 10^{6} \;\text{m}\cdot \text{s}^{-1}$ from the question;

$\Delta p = m\cdot v \\ \phantom{\Delta p} = 0.01 \times 10^{6} \; \text{m} \cdot \text{s}^{-1} \times 9.11 \times 10^{-31} \; \text{kg}\\\phantom{\Delta p} = 9.11 \times 10^{-27} \; \text{kg} \cdot \text{m}\cdot \text{s}^{-1}$

Convert the unit of the Planck's constant to base SI units (kg, m, s, etc.) if it was provided in derived units such as joules. Doing so would allow for a dimension analysis on the accuracy of the result.

$h = 6.63 \times 10^{-34} \; \text{J} \cdot \text{s}\\\phantom{h} = 6.63 \times 10^{-34} \; (\text{N}\cdot \text{m}) \cdot \text{s} \\\phantom{h} = 6.63 \times 10^{-34} \; ((\text{kg} \cdot \text{m}\cdot \text{s}^{-2}) \cdot \text{m}) \cdot \text{s}\\\phantom{h} = 6.63 \times 10^{-34} \; \text{kg} \cdot \text{m}^{2} \cdot \text{s}^{-1}$

Apply the Uncertainty Principle:

$\Delta x = h/ (4 \pi \cdot \Delta p)\\\phantom{\Delta x} = 6.63 \times 10^{-34} \; \text{kg} \cdot \text{m}^{2} \cdot \text{s}^{-1} / (4 \pi \cdot 9.11\times 10^{-27} \; \text{kg} \cdot \text{m}\cdot \text{s}^{-1})\\\phantom{\Delta x} = 5.79 \times 10^{-9} \; \text{m}$ .

Dimensional analysis:

$\Delta x$ resembles the standard deviation of a position measurement. It is expected to have a unit of meter, which is the same as that of position.

3 0

3 years ago

IN DESPERATE NEED OF HELP (I'll give you brainliest and all)

Anna35 [415]

Attached is a word document that contains a picture of the drawing as well as the explanation. Let me know if the picture is not showing up or if my hand writing is too hard to read so that I can type the explanation in the comments for this answer.

the major points for the answer was that the Sn²⁺ is reduced while the Cr is oxidized and that the Sn electrode is the cathode while the Cr electrode is the anode. The electrons travel from the anode to the cathode while the anions travel from the cathode to the anode.

I hope this helps. Let me know if anything is unclear or if you want me to explain anything further.

Download docx

4 0

4 years ago