All categories

3 years ago

What kingdom is Spirogyra in?

Chemistry

1 answer:

jasenka [17]3 years ago

8 0

Protista .................................

You might be interested in

A plane takes 230 passengers from New York to Chicago in 3 hours.

devlian [24]

Answer:263mph

Explanation:

3 0

2 years ago

PLEASE HELP I got this wrong on an exam but got it wrong and i don’t know why!

lord [1]

Answer:

D.5,55cm+/-0,005cm

Explanation:

so this is the answer

5 0

3 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

Write a covalent compound formed by nitrogen and oxygen. what is its Lewis structure

iragen [17]

Answer:

Two covalent bonds form between the two oxygen atoms because oxygen requires two shared electrons to fill its outermost shell. Nitrogen atoms will form three covalent bonds (also called triple covalent) between two atoms of nitrogen because each nitrogen atom needs three electrons to fill its outermost shell.

5 0

3 years ago

A forward reaction in which adding heat decreases product formation is _________, while a forward reaction in which adding heat

ELEN [110]

I believe the correct answer from the choices listed above is option A. <span>A forward reaction in which adding heat decreases product formation is exothermic, while a forward reaction in which adding heat increases product formation is endothermic. Exothermic would mean that heat is being released by the process while the opposite is called endothermic in which it absorbs heat.</span>

3 0

4 years ago