diff --git a/tensornetwork/tests/network_operations_test.py b/tensornetwork/tests/network_operations_test.py
index 189c08594..4b13d5656 100644
--- a/tensornetwork/tests/network_operations_test.py
+++ b/tensornetwork/tests/network_operations_test.py
@@ -15,6 +15,7 @@
 import tensornetwork as tn
 import pytest
 import numpy as np
+from tensornetwork.backends.base_backend import BaseBackend
 
 
 def test_split_node_full_svd_names(backend):
@@ -334,3 +335,89 @@ def test_switch_backend(backend):
   nodes = [a, b, c]
   tn.switch_backend(nodes, backend)
   assert nodes[0].backend.name == backend
+
+
+def test_norm_of_node_without_backend_raises_error():
+  node = np.random.rand(3, 3, 3)
+  with pytest.raises(AttributeError):
+    tn.norm(node)
+
+
+def test_conj_of_node_without_backend_raises_error():
+  node = np.random.rand(3, 3, 3)
+  with pytest.raises(AttributeError):
+    tn.conj(node)
+
+
+def test_transpose_of_node_without_backend_raises_error():
+  node = np.random.rand(3, 3, 3)
+  with pytest.raises(AttributeError):
+    tn.transpose(node, permutation=[])
+
+
+def test_split_node_of_node_without_backend_raises_error():
+  node = np.random.rand(3, 3, 3)
+  with pytest.raises(AttributeError):
+    tn.split_node(node, left_edges=[], right_edges=[])
+
+
+def test_split_node_qr_of_node_without_backend_raises_error():
+  node = np.random.rand(3, 3, 3)
+  with pytest.raises(AttributeError):
+    tn.split_node_qr(node, left_edges=[], right_edges=[])
+
+
+def test_split_node_rq_of_node_without_backend_raises_error():
+  node = np.random.rand(3, 3, 3)
+  with pytest.raises(AttributeError):
+    tn.split_node_rq(node, left_edges=[], right_edges=[])
+
+
+def test_split_node_full_svd_of_node_without_backend_raises_error():
+  node = np.random.rand(3, 3, 3)
+  with pytest.raises(AttributeError):
+    tn.split_node_full_svd(node, left_edges=[], right_edges=[])
+
+
+def test_reachable_raises_value_error():
+  with pytest.raises(ValueError):
+    tn.reachable({})
+
+
+def test_check_correct_raises_value_error_1(backend):
+  a = tn.Node(np.random.rand(3, 3, 3), backend=backend)
+  b = tn.Node(np.random.rand(3, 3, 3), backend=backend)
+  edge = a.edges[0]
+  edge.node1 = b
+  edge.node2 = b
+  with pytest.raises(ValueError):
+    tn.check_correct({a, b})
+
+
+def test_check_correct_raises_value_error_2(backend):
+  a = tn.Node(np.random.rand(3, 3, 3), backend=backend)
+  b = tn.Node(np.random.rand(3, 3, 3), backend=backend)
+  edge = a.edges[0]
+  edge.axis1 = -1
+  with pytest.raises(ValueError):
+    tn.check_correct({a, b})
+
+
+def test_get_all_nodes(backend):
+  a = tn.Node(np.random.rand(3, 3, 3), backend=backend)
+  b = tn.Node(np.random.rand(3, 3, 3), backend=backend)
+  edge = tn.connect(a[0], b[0])
+  assert tn.get_all_nodes({edge}) == {a, b}
+
+
+def test_contract_trace_edges(backend):
+  a = tn.Node(np.random.rand(3, 3, 3), backend=backend)
+  with pytest.raises(ValueError):
+    tn.contract_trace_edges(a)
+
+
+def test_switch_backend_raises_error(backend):
+  a = tn.Node(np.random.rand(3, 3, 3))
+  a.backend = BaseBackend()
+  with pytest.raises(NotImplementedError):
+    tn.switch_backend({a}, backend)