Examples of exponential decay in the real-world.

A chemical change has occured if the number of atoms is greater after the reaction than it was before the reaction.

diamong [38]

Answer:

False

Explanation:

It is not correct to assert that a chemical change has occurred if the number of atoms is greater after the reaction than it was before the reaction.

For every chemical reaction, the law of conservation of mass must be strictly adhered.

The law states that "during a chemical reaction, matter is neither created nor destroyed, atoms are simply rearranged".

By the virtue of this law, the number of atoms at the beginning and the end of the reaction must remain the same for this law to be applicable.

8 0

2 years ago

Elements can be described by various properties, and identified by their boiling and melting points. For example, gold melts at

aleksandr82 [10.1K]

Answer:

Explanation:

Melting and boiling point variations are not clear (do not have uniform pattern) in periodic table. But we can see, some elements have higher melting and boiling points and some have less. Here we study melting and boiling points of s, p, d blocks elements. IVAth group elements (C,Si) show high melting and boiling points because they have covalent gigantic lattice structures.

5 0

2 years ago

Read 2 more answers

The mass percent of oxygen in CaO is what

TEA [102]

Add the reltive atomic mass of Ca and O which are 40 and 16 respectively after addition we get molecular mass of CaO which is 40+16=56 now divide atomic mass of O by molecular mass of CaO and multiply it with 100 as show n 16/56 *100=28.57%

5 0

2 years ago

Be sure to answer all parts. Part 1 out of 2 how many electrophilic centers are present in acetyl chloride (ch3cocl)?

natima [27]

<h3>Answer:</h3>

There is One electrophilic center in acetyl chloride.

<h3>Explanation:</h3>

Electrophile is defined as any specie which is electron deficient and is in need of electrons to complete its electron density or octet. The main two types of electrophiles are those species which either contain positive charge (i.e. NO₂⁺, Cl⁺, Br⁺ e.t.c) or partial positive charge like that contained by the sp² hybridized carbon of acetyl chloride shown below in attached picture.

In acetyl chloride the partial positive charge on sp² hybridized carbon is generated due to its direct bonding to highly electronegative elements *with partial negative charge) like oxygen and chlorine, which tend to pull the electron density from carbon atom making it electron deficient and a good electrophile for incoming nucleophile as a center of attack.