Which of the following is a characteristic of a strong base

This chart lists four elements from the periodic table.

aksik [14]

Iodine and Calcium is the correct answer

3 0

3 years ago

ow does the food chain start? A Plant life uses energy from the sun to make food. B Insects like grasshoppers eat plant life. C

Natali [406]

A is the answer! I’m pretty sure hopefully i helped!!

5 0

2 years ago

I have 2 samples of solid chalk (aka calcium carbonate). Sample A has a total mass of 4.12 g and Sample B has a total mass of 19

IRINA_888 [86]

Answer:

A) Sample B has more calcium carbonate molecules

Explanation:

M = Molar mass of calcium carbonate = 100.0869 g/mol

$N_A$ = Avogadro's number = $6.022\times 10^{23}\ \text{mol}^{-1}$

For the 4.12 g sample

Moles of a substance is given by

$n=\dfrac{m}{M}\\\Rightarrow n=\dfrac{4.12}{100.0869}\\\Rightarrow n=0.0411\ \text{mol}$

Number of molecules is given by

$nN_A=0.0411\times 6.022\times 10^{23}=2.48\times 10^{22}\ \text{molecules}$

For the 19.37 g sample

$n=\dfrac{19.37}{100.0869}\\\Rightarrow n=0.193\ \text{mol}$

Number of molecules is given by

$nN_A=0.193\times 6.022\times 10^{23}=1.16\times 10^{23}\ \text{molecules}$

$1.16\times 10^{23}\ \text{molecules}>2.48\times 10^{22}\ \text{molecules}$

So, sample B has more calcium carbonate molecules.

The ratio of the elements of carbon, oxygen, calcium atoms, ions, has to be same in both the samples otherwise the samples cannot be considered as calcium carbonate. Same is applicable for impurities. If there are impurites then the sample cannot be considered as calcium carbonate.

7 0

3 years ago

1. The forks shown are made of silver (Ag). Some of the silver forks

Anon25 [30]

Answer:

Corrosion

Explanation:

Silver, although known as a nobble metal, is also subject to corrosion process such as having silver tarnish when exposed to sulfur and air.

Tarnishing occurs on the surfaces of some metals such as brass, copper, and silver, which results in a corroded layer. Silver tarnish occurs from the chemical reaction that takes place when silver is exposed to sulfur which results in the formation of black Ag₂S

In order to restore the original silver surface, the silver tarnish (silver sulfide) layer is removed.

We have the statement presented here as follows;

The forks shown are made of silver (Ag). Some of the silver forks shown have lost their luster - they have become tarnished. This is an example of <u>Corrosion.</u>

4 0

2 years ago

How many mol of hydrogen are needed to double the volume occupied by 0.34 mol of hydrogen,

natima [27]

Answer:

0.68

Explanation:

Number of moles is directly propotionalto the volume at standard condition.

6 0

3 years ago