What type of mirror could have resulted in the image of the giraffe above?

PLeaseee ITS Timedddd + BrainlIESTT

zmey [24]

Answer:

d. 12.3 grams of Al2O3

Explanation:

Based on the reaction:

4Al + 3O2 → 2Al2O3

<em>Where 4 moles of Al reacts in excess of oxygen to produce 2 moles of aluminium oxide.</em>

<em />

To solve this question we must find the moles of Aluminium. With these moles we can find the moles of aluminium oxide using the reaction:

<em>Moles Al -Molar mass: 26.9815g/mol-</em>

6.50g * (1mol / 26.9815g) = 0.241 moles Al

<em>Mass Al₂O₃ -Molar mass: 101.96g/mol-</em>

0.241 moles Al * (2 mol Al2O3 / 4 mol Al) = 0.120 moles Al2O3

0.120 moles Al2O3 * (101.96g / mol) =

12.3g of Al2O3 are produced.

Right answer is:

<h3>d. 12.3 grams of Al2O3 </h3>

8 0

2 years ago

Heavy nuclides with too few neutrons to be in the band of stability are most likely to decay by what mode?

Margarita [4]

Answer:

Positron emission

Explanation:

Positron emission involves the conversion of a proton to a neutron. This process increases the mass number of the daughter nucleus by 1 while its atomic number remains the same. The new neutron increases the number of neutrons present in the daughter nucleus hence the process increases the N/P ratio.

A positron is usually ejected in the process together with an anti-neutrino to balance the spins.

6 0

2 years ago

The diagram below shows an electromagnet. Using your scientific knowledge, state the device that is used to measure the potentia

weeeeeb [17]

Voltmeter is the device that is used to measure the potential difference across the battery.

<h2>What are the usage of voltmeter?</h2><h3 /><h3>Usage of Voltmeter</h3>

Voltmeter is an instrument that measures voltages of both direct and alternating electric current. On a scale of voltmeter usually graduated in volts, millivolts (0.001 volt), or kilovolts (1,000 volts).

Voltmeter is connected in parallel form. It has a high resistance so that it takes negligible current from the circuit so we can conclude that Voltmeter is the device that is used to measure the potential difference across the battery.

8 0

2 years ago

Calculate the vapor pressure of a solution made by dissolving 11.1 g Ca(OH)2 in 1 102 g of water at 25 °C. Vapor pressure of pur

Levart [38]

Answer:

23.15 mmHg.

Explanation:

To solve this question you need to understand that part of Raoult's law in your Chemistry textbook. So, let us delve right into the solution of the question.

We are given parameters such as the mass of Ca(OH)2 to be = 11.1 grams, mass of solvent = 102 grams, the Vapor pressure of pure water= 23.76 mm Hg, temperature = 25°C and vapour pressure of the solution= ??.

The molar mass of Ca(OH)2= 74 g/mol.

The first thing to do is to find the number of moles of Ca(OH)2 and that of water from the formula below;

Mass/ molar mass = Number of moles.

===> Number of moles, n= 11.1/ 74.

Number of moles = 0.15 moles Ca(OH)2.

===> Number of moles, n= 102/ 18.

Number of moles, n= 5.67 moles of water.

Next, we add the two moles together to find the solvent mile fraction since vapour pressure is proportional to mole fraction.

Then;

0.15 + 5.67 = 5.82.

Therefore, 5.67/ 5.82= 0.97.

Hence the vapor pressure of a solution = 0.97 × 23.76.

vapor pressure of a solution = 23.15 mmHg.

4 0

3 years ago

Read 2 more answers

The ion n3− has _____ protons and _____ electrons.enter your answers as integers separated by a comma.

bearhunter [10]

The ion N³⁻ is called the azide ion. In its neutral state, it occurs as the element Nitrogen. The atomic number of Nitrogen is 7. When it turns into an anion (negatively charged ion), it gains 3 more electrons. That's why its net charge becomes -3. It means that the protons is still 7, but the electrons are now 10.

Overall charge = +7 + -10 = -3

5 0

3 years ago

Read 2 more answers