Answer: C. no new substances
are formed<span>
</span><span>
<span>In the
physical change of matter, there is no new substance that is formed. It is only
the appearance of the matter that is being changed and not its chemical
composition. Cutting, tearing and grinding are only some of the examples that
exhibit physical change. </span></span>
Answer: D, hydrolysis
Hydrolysis is any chemical reaction in which a molecule of water ruptures one or more chemical bonds. The term is used broadly for substitution, elimination, and fragmentation reactions in which water is the nucleophile.
Explanation:
a) when zinc burnt in oxygen.
2Zn + O2 -----∆-----> 2ZnO(black residue)
b) when carbon burnt in oxygen.
C+O2----∆---> CO2.
c) when sulphur burnt in oxygen.
S+O2-----∆-----> SO2.
d) when Calcium burnt in oxygen.
2Ca+O2-----∆-----> 2CaO(black residue)
e) when Magnesium burnt in oxygen.
2Mg+O2-----∆----> 2MgO.
f) when sodium burnt in oxygen.
4Na+O2----∆-----> 2Na2O.
hope all these reactions help you.
Answer:
<h2>The answer is option A</h2>
Explanation:
The mass of a substance when given the density and volume can be found by using the formula
<h3>mass = Density × volume</h3>
From the question
volume of object = 7 cm³
density = 5 g/cm³
The mass of the object is
mass = 5 × 7
We have the final answer as
<h2>35 g</h2>
Hope this helps you
Answer:
From the periodic table, Atomic number of fluorine is 7 and atomic mass is 19
