Give one example of a physical change and one example of a chemical change from real life.

What element from the "Periodic Table" is named after an "Austrian Scientist"??

soldier1979 [14.2K]

Answer:

Should be either mendele or fermium

maybe lawrencium not sure but I think it’s lawrencium! Sorry if wrong heh

Explanation: <u><em>really trying to help! If it’s wrong super sorry!!!</em></u>

3 0

3 years ago

Consider the following reaction

aliina [53]

Answer:

d, 40 dm3.

Explanation:

According to Avogadro's law, the mole ratio of chemicals in a reaction is equal to the ratio of volumes of chemicals reacted (for gas).

From the equation, the mole ratio of N2 : H2 : NH3 = 1 : 3 : 2, meaning 1 mole of N2 reacts completely with 3 moles of H2 to give 2 moles of NH3, the ratio of volume required is also equal to 1 : 3 : 2.

Considering both N2 and H2 have 30dm3 of volume, but 1 mole of N2 reacts completely with 3 moles of H2, so we can see H2 is limiting while N2 is in excess. Using the ratio, we can deduce that 10dm3 equals to 1 in ratio (because 3 moles ratio = 30dm3).

With that being said, all H2 has reacted, meaning there's no volume of H2 left. 2 moles of NH3 is produced, meaning the volume of NH3 produced = 10 x 2 = 20 dm3. (using the ratio again)

1 mole of N2 has reacted, meaning from the 30dm3, only 10 dm3 has reacted. This also indicate that 20 dm3 of N2 has not been reacted.

So at the end, the mixture contains 20dm3 of NH3, and 20 dm3 of unreacted N2. Hence, the answer is d, 40 dm3.

7 0

3 years ago

Give the name of the products formed

attashe74 [19]

Answer:

With Br2 - Bromobenzene

With Cl2 - Chlorobenzene

With HNO3- Nitrobenzene

With H2SO4 - Benzenesulphonic acid

With HCOCl - Benzoyl chloride

With 1-chloro-2,2-dimethylpropane - 2,2dimethyl-1-phenyl propane

Explanation:

The common thread joining all these reactions is that they are all electrophillic reactions. They are so called because the attacking agents in each reagent is an electrophile. Electrophiles are species that have electron deficient centers and are known to attack molecules that are high in electron density at regions of high electron density.

The benzene molecule has rich electron density. Any substituents that donates electrons to the ring improves the likelihood that benzene will undergo electrophillic substitution reactions while electron withdrawing substituents decrease the likelihood that benzene will undergo electrophillic substitution reactions.

The names of the compounds formed when benzene undergoes electrophillic reaction with the attacking agents listed in the question are displayed in the answer section.

7 0

3 years ago

Natural gas (CH4) has a molar mass of 16.0 g/mole. You started out the day with a tank containing 200.0 g of natural gas. At the

hodyreva [135]

Considering the definition of molar mass, the moles of gas used are 10.625 moles.

<h3>Definition of molar mass</h3>

The molar mass of substance is a property defined as its mass per unit quantity of substance, in other words, molar mass is the amount of mass that a substance contains in one mole.

<h3>Amount of moles used</h3>

Natural gas has a molar mass of 16.0 g/mole.

You started out the day with a tank containing 200.0 g of natural gas. So, you can apply the following rule of three: If by definition of molar mass 16 grams are contained in 1 mole, 200 grams are contained in how many moles?

$amount of moles at the beginning=\frac{200 gramsx1 mole}{16 grams}$

<u><em>amount of moles at the beginning= 12.5 moles</em></u>

At the end of the day, your tank contains 30.0 g of natural gas. So, you can apply the following rule of three: If by definition of molar mass 16 grams are contained in 1 mole, 30 grams are contained in how many moles?

$amount of moles at the end=\frac{30 gramsx1 mole}{16 grams}$