Answer:
This is because of the release of hydrogen gas in the reaction.
Explanation:
Metals react with water and produce a metal oxide and hydrogen gas. It also starts floating due to the bubbles of hydrogen gas sticking to its surface.
For eg:
<u>2Mg. + 2H2O --------> 2MgOH + H2</u>
Here,
Metal taken is <u>magnesium(2Mg)</u> which when reacts with <u>water(2H2O)</u> to form its <u>oxide form (2MgOH)</u> and <u>hydrogen gas(H2)</u> is released which comes outside water as bubbles.
Answer:
The volume is 4.13793 L
Explanation:
Density is a quantity that expresses the relationship between the mass and the volume of a body, so it is defined as the quotient between the mass and the volume of a body:
Density is a characteristic property of every body or substance.
The most commonly used units of density are 
or 
for solids, and 
or 
for liquids and gases.
In this case, you know:
- density= 0.87
- mass= 3.6 kg= 3,600 g (being 1 kg=1,000 g)
- volume= ?
Replacing:
Solving:
volume= 4,137.93 mL
Being 1,000 mL=1 L, then volume= 4,137.93 mL= 4.13793 L
<u><em>The volume is 4.13793 L</em></u>
Answer:Sodium ions
Explanation:
The membrane potential of most cells is negative, when sodium ions enters the cells, it can reverse the polarity and makes it positively charge.
solution:
You need to find the frequency, and they have already given you the wavelength. And since you already know the speed of light, you can use formula (2) to answer this problem. Remember to convert the nano meters to meters because the speed of light is in meters. 
Using electronegativity difference is a good guide to the ionic/ covalent nature. Large differences indicate greater ionic character, small differences more covalent character. The larger the difference in electronegativity the more ionic properties a bond is said to have. The smaller the difference in electronegativity the more covalent properties a bond is said to have.
Ionic bonding is formed through electrostatic attraction between a cation and anion. Foe example, Sodium fluoride has ionic bonding because it is composed by sodium and Fluorine (a non metal). On the other hand, covalent bonding is characterized by atoms sharing pairs of electrons. For example; methane has covalent bonding; carbon has 4 valence electrons and hydrogen has 1; when they bond they have a total of 8 electrons and satisfies the octet rule.
