Calculate how many moles are present in 545 cm3 CH4 at STP.

If this decay has a half life of 2.60 years, what mass of 72.5 g of sodium 22 will remain after 15.6 years

Vlad1618 [11]

Sodium-22 remain : 1.13 g

<h3>Further explanation </h3>

The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.

Usually, radioactive elements have an unstable atomic nucleus.

General formulas used in decay:

$\large{\boxed{\bold{N_t=N_0(\dfrac{1}{2})^{T/t\frac{1}{2} }}}$

T = duration of decay

t 1/2 = half-life

N₀ = the number of initial radioactive atoms

Nt = the number of radioactive atoms left after decaying during T time

half-life = t 1/2=2.6 years

T=15.6 years

No=72.5 g

$\tt Nt=72.5.\dfrac{1}{2}^{15.6/2.6}\\\\Nt=72.5.\dfrac{1}{2}^6\\\\Nt=1.13~g$

8 0

4 years ago

Use you observation to determine which polymorph is in the customer’s returned chocolate sample.

Assoli18 [71]

Cocoa butter, the fat in chocolate, can crystallize in any one of 6 different forms (polymorphs, as they are called). Unfortunately, only one of these, the beta crystal (or Form V), hardens into the firm, shiny chocolate that cooks want. Form VI is also a stable hard crystal, but only small amounts of it form from the good beta (Form V) crystals upon lengthy standing. When you buy commercial chocolate it is in the form of beta crystals.

When you melt chocolate and get it above 94° F, you melt these much desired beta crystals and other types of crystals can set up. If you simply let melted chocolate cool, it will set up in a dull, soft, splotchy, disgusting-looking form. Even the taste is different. Fine chocolate has a snap when you break it and a totally different mouthfeel from the other cocoa butter forms.

hope it's help you......!!!!!!! 

please mark as brain list.......!!!!!!! 

#rishu

7 0

3 years ago

Functions of the following ingredients in the production of dairy products.ii. Enzyme in cheese

Serjik [45]

Answer:

sugar in melk

Explanation:

cow eat sugar then make sugar :)

5 0

3 years ago

How did the grsnd cayon form

Alchen [17]

Answer:

erosion

Explanation:

4 0

3 years ago

Most solids

Daniel [21]

Most solids a) are dense and difficult to compress.

Most solids are closely compacted, their molecules are close together and vibrate. They don't move freely like gas or water molecules do.
They are difficult to be squeezed or flattened.

6 0

3 years ago