Answer:
9,000, 100 has 7 significant figures
Explanation:
Let us assume that the ring is a size 7 ring, which has a circumference of 54.3 millimeters. Converting this to centimeters, the circumference of the ring is:
54.3 mm = 5.43 cm
Now, we determine the number of gold atoms that will be present in this:
5.43 / 1 x 10⁻⁹
There will be 5.43 x 10⁹ atoms
We now determine the number of moles this is by:
one mole = 6.02 x 10²³ atoms
Moles = 5.43 x 10⁹ / 6.02 x 10²³
Moles = 9.01 x 10⁻¹⁵ moles
The molar mass of gold is 197 g/mol
The mass is 9.01 x 10⁻¹⁵ * 197
The mass of the strand is 1.76 x 10⁻¹² grams
Answer:
Collid
Explanation:
Toothpaste is a colloid, because it's part solid and part liquid. ... A colloid is a heterogeneous mixture of two substances of different phases. Shaving cream and other foams are gas dispersed in liquid. Jello, toothpaste, and other gels are liquid dispersed in solid.
Hey there!
Molar mass NaCl = 58.44 g/mol
Number of moles
n = mass of solute / molar mass
n = 59.76 / 58.44
n = 1.0225 moles of NaCl
Volume in liters:
270 mL / 1000 => 0.27 L
Therefore:
M = number of moles / volume ( L )
M = 1.0225 / 0.27
= 3.78 M
Hope that helps!
acids give away protons (H+), bases accept protons, conjugate bases are what u get when when you take the protons from the acid, and conjugate acids are what u get when you add the protons to the base.
so for (a) the C5H5N is the base, water is the acid, C5H5NH+ is the conj acid, OH- is the conj base
(b) HNO3 is the acid, H2O is the base, hydronium ion is the conj. acid, NO3- is the conj base.
